SERVER-10325: support system and user flags for mongos collstats
SERVER-13429 Use logging system in mongod signal handlers, test exit logging.

Still not really safe for signal handlers, but no worse than before,
and correctly logs to the log file/syslog, so an improvement.
SERVER-13438 Handle syslog case of systemLog.destination properly
SERVER-13379 Fixing parsed naming of jsonp option in mongos
SERVER-13429 Eliminate rawOut and related functions
SERVER-13429 Remove printStackAndExit

All of the functions in signal_handlers.cpp were broken when logfiles or
syslog were in use. This commit removes them and all callers. The files were
left in place for a later commit to fill them back in with a unified signal
handling system.
SERVER-13429 unify signal handling between mongos and mongod
SERVER-13429 Update exit_logging.js to also test mongos exit logging.
SERVER-13448 broadcast updates/deletes to all shards when more than one targeted
SERVER-12242 SERVER-12244 Fix typo in compact/reIndex error messages

The error messages originally were incorrectly swapped with one
another.
Revert "SERVER-13383 validateKeyPattern allow only numeric/string key types"

This reverts commit be9cd7b940531fe8a46e669155c81ca14e5189b0.
SERVER-13459 migration rollback needs to use original metadata
SERVER-13459 improved migration rollback test