remove php-apc since it keeps segfaulting apache

======= Backtrace: =========
/lib/x86_64-linux-gnu/libc.so.6(+0x75ab6)[0x7f7e8112fab6]
/lib/x86_64-linux-gnu/libc.so.6(cfree+0x6c)[0x7f7e811347ec]
/usr/lib/apache2/modules/libphp5.so(destroy_zend_class+0x255)[0x7f7e7cddc515]
/usr/lib/apache2/modules/libphp5.so(zend_hash_clean+0x70)[0x7f7e7cdf41a0]
/usr/lib/php5/20100525/apc.so(apc_interned_strings_shutdown+0x20)[0x7f7e731db7a0]
/usr/lib/php5/20100525/apc.so(apc_module_shutdown+0x12a)[0x7f7e731d50ba]
/usr/lib/php5/20100525/apc.so(+0xb70f)[0x7f7e731ca70f]
/usr/lib/apache2/modules/libphp5.so(+0x36d6b3)[0x7f7e7cded6b3]
/usr/lib/apache2/modules/libphp5.so(+0x372a85)[0x7f7e7cdf2a85]
/usr/lib/apache2/modules/libphp5.so(zend_hash_graceful_reverse_destroy+0x18)[0x7f7e7cdf4278]
/usr/lib/apache2/modules/libphp5.so(+0x365f3e)[0x7f7e7cde5f3e]
/usr/lib/apache2/modules/libphp5.so(php_module_shutdown+0x2a)[0x7f7e7cd86f2a]
/usr/lib/apache2/modules/libphp5.so(php_module_shutdown_wrapper+0x9)[0x7f7e7cd86fe9]
/usr/lib/apache2/modules/libphp5.so(+0x40e931)[0x7f7e7ce8e931]
/usr/lib/libapr-1.so.0(+0x20074)[0x7f7e8167d074]
/usr/lib/libapr-1.so.0(apr_pool_destroy+0x57)[0x7f7e8167be89]
/usr/sbin/apache2(+0x5af6e)[0x7f7e81f76f6e]
/usr/sbin/apache2(+0x5b35c)[0x7f7e81f7735c]
/usr/sbin/apache2(+0x5ba2a)[0x7f7e81f77a2a]
/usr/sbin/apache2(+0x5bae7)[0x7f7e81f77ae7]
/usr/sbin/apache2(ap_mpm_run+0x884)[0x7f7e81f78464]
/usr/sbin/apache2(main+0xc84)[0x7f7e81f4d6a4]
/lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xfd)[0x7f7e810d8ead]
/usr/sbin/apache2(+0x31759)[0x7f7e81f4d759]
======= Memory map: ========
Disable errbit.nix.is due to scary errors (see attached)

We keep getting these errors in Apache's error.log:

    terminate called after throwing an instance of 'boost::exception_detail::clone_impl<boost::exception_detail::error_info_injector<boost::lock_error> >'
      what():  Invalid argument (22)
    [ pid=32456, timestamp=1333483832 ] Process aborted! signo=SIGABRT(6), reason=SI_TKILL, signal sent by PID 32456 with UID 0, backtrace available.
    --------------------------------------
    [ pid=32456 ] Backtrace with 34 frames:
    PassengerHelperAgent[0x52b645]
    /lib/x86_64-linux-gnu/libpthread.so.0(+0xf030)[0x7f030c451030]
    /lib/x86_64-linux-gnu/libc.so.6(gsignal+0x35)[0x7f030b94e475]
    /lib/x86_64-linux-gnu/libc.so.6(abort+0x180)[0x7f030b9516f0]
    /usr/lib/x86_64-linux-gnu/libstdc++.so.6(_ZN9__gnu_cxx27__verbose_terminate_handlerEv+0x11d)[0x7f030c19f4fd]
    /usr/lib/x86_64-linux-gnu/libstdc++.so.6(+0x62606)[0x7f030c19d606]
    /usr/lib/x86_64-linux-gnu/libstdc++.so.6(+0x61719)[0x7f030c19c719]
    /usr/lib/x86_64-linux-gnu/libstdc++.so.6(__gxx_personality_v0+0x481)[0x7f030c19d251]
    /lib/x86_64-linux-gnu/libgcc_s.so.1(+0xfd6b)[0x7f030bcb2d6b]
    /lib/x86_64-linux-gnu/libgcc_s.so.1(_Unwind_Resume+0x68)[0x7f030bcb31c8]
    PassengerHelperAgent(_ZN5boost5mutex4lockEv+0x64)[0x4cc482]
    PassengerHelperAgent(_ZN5boost10lock_guardINS_5mutexEEC1ERS1_+0x2a)[0x4ff6dc]
    PassengerHelperAgent(_ZN9Passenger5Timer5startEv+0x23)[0x4d2ac3]
    PassengerHelperAgent(_ZN18TimerUpdateHandler18clientDisconnectedERN9Passenger13MessageServer19CommonClientContextERN5boost10shared_ptrINS1_13ClientContextEEE+0x40)[0x4fbf04]
    PassengerHelperAgent(_ZN9Passenger13MessageServer29DisconnectEventBroadcastGuardD1Ev+0x91)[0x4d9a3d]
    PassengerHelperAgent(_ZN9Passenger13MessageServer22clientHandlingMainLoopENS_14FileDescriptorE+0xca5)[0x4db4bb]
    PassengerHelperAgent(_ZNK5boost4_mfi3mf1IvN9Passenger13MessageServerENS2_14FileDescriptorEEclEPS3_S4_+0x7a)[0x527cbe]
    PassengerHelperAgent(_ZN5boost3_bi5list2INS0_5valueIPN9Passenger13MessageServerEEENS2_INS3_14FileDescriptorEEEEclINS_4_mfi3mf1IvS4_S7_EENS0_5list0EEEvNS0_4typeIvEERT_RT0_i+0x77)[0x5261af]
    PassengerHelperAgent(_ZN5boost3_bi6bind_tIvNS_4_mfi3mf1IvN9Passenger13MessageServerENS4_14FileDescriptorEEENS0_5list2INS0_5valueIPS5_EENS9_IS6_EEEEEclEv+0x39)[0x523b69]
    PassengerHelperAgent(_ZN5boost6detail8function26void_function_obj_invoker0INS_3_bi6bind_tIvNS_4_mfi3mf1IvN9Passenger13MessageServerENS7_14FileDescriptorEEENS3_5list2INS3_5valueIPS8_EENSC_IS9_EEEEEEvE6invokeERNS1_15function_bufferE+0x23)[0x51e700]
    PassengerHelperAgent(_ZNK5boost9function0IvEclEv+0x52)[0x4ffea4]
    PassengerHelperAgent(_ZN3oxt20dynamic_thread_group11thread_mainERN5boost8functionIFvvEEEPNS0_13thread_handleE+0x38)[0x4d12b8]
    PassengerHelperAgent(_ZNK5boost4_mfi3mf2IvN3oxt20dynamic_thread_groupERNS_8functionIFvvEEEPNS3_13thread_handleEEclEPS3_S7_S9_+0x6b)[0x527947]
    PassengerHelperAgent(_ZN5boost3_bi5list3INS0_5valueIPN3oxt20dynamic_thread_groupEEENS2_INS_8functionIFvvEEEEENS2_IPNS4_13thread_handleEEEEclINS_4_mfi3mf2IvS4_RS9_SC_EENS0_5list0EEEvNS0_4typeIvEERT_RT0_i+0x88)[0x525c86]
    PassengerHelperAgent(_ZN5boost3_bi6bind_tIvNS_4_mfi3mf2IvN3oxt20dynamic_thread_groupERNS_8functionIFvvEEEPNS5_13thread_handleEEENS0_5list3INS0_5valueIPS5_EENSE_IS8_EENSE_ISB_EEEEEclEv+0x39)[0x523627]
    PassengerHelperAgent(_ZN5boost6detail8function26void_function_obj_invoker0INS_3_bi6bind_tIvNS_4_mfi3mf2IvN3oxt20dynamic_thread_groupERNS_8functionIFvvEEEPNS8_13thread_handleEEENS3_5list3INS3_5valueIPS8_EENSH_ISB_EENSH_ISE_EEEEEEvE6invokeERNS1_15function_bufferE+0x23)[0x51dbb4]
    PassengerHelperAgent(_ZNK5boost9function0IvEclEv+0x52)[0x4ffea4]
    PassengerHelperAgent(_ZN3oxt6thread11thread_mainEN5boost8functionIFvvEEENS1_10shared_ptrINS0_11thread_dataEEE+0x62)[0x4cd7cc]
    PassengerHelperAgent(_ZN5boost3_bi5list2INS0_5valueINS_8functionIFvvEEEEENS2_INS_10shared_ptrIN3oxt6thread11thread_dataEEEEEEclIPFvS5_SB_ENS0_5list0EEEvNS0_4typeIvEERT_RT0_i+0x8a)[0x52a8d0]
    PassengerHelperAgent(_ZN5boost3_bi6bind_tIvPFvNS_8functionIFvvEEENS_10shared_ptrIN3oxt6thread11thread_dataEEEENS0_5list2INS0_5valueIS4_EENSD_IS9_EEEEEclEv+0x39)[0x52a83f]
    PassengerHelperAgent(_ZN5boost6detail11thread_dataINS_3_bi6bind_tIvPFvNS_8functionIFvvEEENS_10shared_ptrIN3oxt6thread11thread_dataEEEENS2_5list2INS2_5valueIS6_EENSF_ISB_EEEEEEE3runEv+0x1e)[0x52a09e]
    PassengerHelperAgent(thread_proxy+0x6b)[0x54c93c]
    /lib/x86_64-linux-gnu/libpthread.so.0(+0x6b50)[0x7f030c448b50]
    /lib/x86_64-linux-gnu/libc.so.6(clone+0x6d)[0x7f030b9f490d]
    --------------------------------------
    [ pid=32456 ] Dumping a more detailed backtrace with crash-watch ('gem install crash-watch' if you don't have it)...
    sh: 1: crash-watch: not found
    *** Exception Errno::EPIPE in spawn manager (Broken pipe) (process 32461, thread #<Thread:0x00000001cff0c0>):
    	from /home/passenger/.rvm/gems/ruby-1.9.3-p125/gems/passenger-3.0.11/lib/phusion_passenger/message_channel.rb:278:in `write'
    	from /home/passenger/.rvm/gems/ruby-1.9.3-p125/gems/passenger-3.0.11/lib/phusion_passenger/message_channel.rb:278:in `write'
    	from /home/passenger/.rvm/gems/ruby-1.9.3-p125/gems/passenger-3.0.11/lib/phusion_passenger/spawn_manager.rb:329:in `send_error_page'
    	from /home/passenger/.rvm/gems/ruby-1.9.3-p125/gems/passenger-3.0.11/lib/phusion_passenger/spawn_manager.rb:277:in `rescue in handle_spawn_application'
    	from /home/passenger/.rvm/gems/ruby-1.9.3-p125/gems/passenger-3.0.11/lib/phusion_passenger/spawn_manager.rb:274:in `handle_spawn_application'
    	from /home/passenger/.rvm/gems/ruby-1.9.3-p125/gems/passenger-3.0.11/lib/phusion_passenger/abstract_server.rb:357:in `server_main_loop'
    	from /home/passenger/.rvm/gems/ruby-1.9.3-p125/gems/passenger-3.0.11/lib/phusion_passenger/abstract_server.rb:206:in `start_synchronously'
    	from /home/passenger/.rvm/gems/ruby-1.9.3-p125/gems/passenger-3.0.11/helper-scripts/passenger-spawn-server:99:in `<main>'
    /home/passenger/sites/errbit.nix.is/shared/bundle/ruby/1.9.1/gems/activesupport-3.0.10/lib/active_support/dependencies.rb:239:in `block in require': iconv will be deprecated in the future, use String#encode instead.
apache2/apache2.conf: set LogLevel to debug

See the previous two patches for why.