SERVER-15012 SubplanStage must check for missing cache data
SERVER-15041 detect StepDownPeriodActive properly
SERVER-15040 initialize our own HeartbeatMemberData when updating config in the TopologyCoordinator
SERVER-14668 Remove d_globals.h/.cpp

They were only used for ClientCursorMonitor startup, so I moved this to be
a singleton task.
SERVER-14413 Fix warnings inside MMAPV1 metadata operations
SERVER-14668 Fix for commit c069fc13a9 which broke OSX build
SERVER-15007 Add epoch check for split and moveChunk
Merge remote-tracking branch 'upstream/master'