Revert "[core] implement streams on chunkqueues"

 - accidental push, patch not finished yet

This reverts commit 74ce55c86061f6110964d7de0cd5adc5f4ccfb57.
[tests] add --valgrind option
Fix comment style (//) and add gnutls to automake distcheck
[core] implement streams on chunkqueues
generic backends
[core] Use streams
[mod_fastcgi]: use backends
[mod_scgi] use backends
[common] implement libev wrapper

 * need a way to mark a watcher as "don't keep the loop alive"
[mod_proxy] use backends
[openssl] use BIO wrappers for streams
[mod_gnutls] stream
[core] register server prepare callbacks
[throttle] rewrite
fix missing li prefixes
fix glib deprecation warnings
[subrequests lua] fix compile warnings. still not working, needs to be ported to stream api.
wait for request body in dynamic backends, cache them on disk
[test] mod_fastcgi: upload 2MiB and check sha1sum
[tests] use 127.0.0.2 as base address