minor: Build 'all' target in 'before_script', not just the driver
minor: expose mongo macros in ycm
CXX-182 initial WriteConcern implementation
CXX-182 tests for WriteConcern class
CXX-182 add OperationException class
CXX-182 integrate WriteConcern into interface
CXX-182 fix existing tests that throw exceptions now
minor: 100k is probably enough, boiling oceans, etc
CXX-182 updates requested after second review
CXX-182 third review updates
CXX-182 comments and minor changes after review
CXX-182 remove comment that is no longer true
CXX-206 Backport server 2.6.0..2.7.0 changes

Files merged manually or fixed up:
 SConstruct
 src/mongo/bson/bsonobj.h
 src/mongo/bson/optime.cpp
 src/mongo/bson/optime.h
 src/mongo/client/connpool.h
 src/mongo/client/dbclientinterface.h
 src/mongo/db/repl/member_state.h
 src/mongo/dbtests/mock/mock_replica_set.cpp
 src/mongo/util/assert_util.h
 src/mongo/util/log.h
 src/mongo/util/time_support.h
CXX-227 Implement hygenic build support
CXX-227 Remove more obsolete items from .gitignore
CXX-227 Clarify comment per review feedback
CXX-227 With hygenic builds, no longer need --prefix in travis
CXX-226 Error out if we fail to find boost headers at configure time
minor: add MacOSX system path for libc++ to ycm_extra_conf
CXX-185 - aggregation helper

Added in an aggregation helper and shims for the DBClientCursor to allow
for the special semantics used for return values.