SERVER-13084: remove some magic DiskLoc calls
SERVER-13084: move iterator into record layer
SERVER-13084: remove some DiskLoc::ref references
move tests from noPassthrough to slow2
remove sayMemoryStatus, which wrote to the log file every 60 seconds
SERVER-13528 Cherry pick fixes for gperftools issue 581

https://code.google.com/p/gperftools/source/detail?r=185bf3fcc36f8cb3839abdfe652f615bfb5306d1
https://code.google.com/p/gperftools/source/detail?r=71a239e559c9ea2300ad0511f8de7077db5369c3
SERVER-13528 After taking gperftools issue 581 fixes, renable OS X debug alloc
SERVER-9358 Prevent logRotate twice in the same second from losing log data
SERVER-12189 Enable libstdc++ debugging features for debug builds when possible
SERVER-13559 Remove legacy debugging flags and honor zero arg invocations of dbg and opt
SERVER-13518 generate _ids in write batches if not set in mongos
SERVER-13518 break child batches up by size or number of documents
SERVER-13518 make sure all tested updates are valid with update exprs
SERVER-13555: comment out storageDetails for now
SERVER-13084: some work on DiskLoc::ext
SERVER-13084: move compact details down into RecordStore layer
SERVER-13512 add mr_drop.js to the skipTests in parallelTester.js
SERVER-13544 Enable gperftools for C++11 builds

The following change was backported:
https://code.google.com/p/gperftools/source/detail?r=18fbc316eebea9db2d7ec41e161c0a3fbb09fa42

Another change we wanted was:
https://code.google.com/p/gperftools/source/detail?r=6287bbbbad8730712cfd1ee28ecc0648cbaa9f94#

However, since that patch must hit every PR/SC instance and the code has evolved from that point
we instead just ran the following two scripts over the gperftools source tree:

find . -type f | xargs egrep -l '"PR\w+"' | xargs perl -pi -e 's|"PR(\w+)"|" PR\1 "|g'
find . -type f | xargs egrep -l '"SC\w+"' | xargs perl -pi -e 's|"SC(\w+)"|" SC\1 "|g'

and then manually fixing up the one reference to GPRIuPTHREAD, which achieved the same result.

Finally, remove the logic preventing mixture of C++11 and gperftools from the build system.
SERVER-13537 better handle numerical overflow of large limit values
SERVER-13557 disallow negated elemMatch value from using an index scan