SERVER-15195 Implement getHostsWrittenTo in ReplicationCoordinatorImpl
SERVER-14567 Implement checkIfWriteConcernCanBeSatisfied in ReplicationCoordinatorImpl
SERVER-14445 Remove waitUpToOneSecondForOptimeChange from ReplicationCoordinator
SERVER-15248 Introduce ScatterGatherAlgorithm interface and ScatterGatherRunner.

The ScatterGatherAlgorithm interface describes operations that a scatter-gather
process must perform.  ScatterGatherRunner uses a ReplicationExecutor to
execute a ScatterGatherAlgorithm.
SERVER-13635: make generic SortedDataInterface unit test
SERVER-15247 GroupCommand::parseRequest() read CodeWScope correctly
SERVER-14444 Implement stepDown functionality in RelicationCoordinatorImpl
SERVER-14600 rename canServeReadsFor() to checkCanServeReadsFor() in the ReplicationCoordinator
SERVER-14508 Rewrite geo parsing using Status
SERVER-10448 change default explain mode from queryPlanner to executionStats
SERVER-14444 Don't call stepDown in ReplicationCoordinatorImpl (yet)
SERVER-1424 (re)smoke tag parsing and new test library, v0

Includes:
- Smoke.py options for filtering by jstest tags
- New resmoke.py test utility in v0 alpha
- Lots of example resmoke configurations
- SCons integration for unittests
- Sample tagged jstests
SERVER-15248 Convert QuorumChecker into a ScatterGatherAlgorithm.
SERVER-15248 Use a ScatterGatherAlgorithm in ElectCmdRunner.
SERVER-15248 Convert FreshnessChecker to use a ScatterGatherAlgorithm.

Also, use completion functions instead of scheduling work on events to handle
election phase transitions in repl_coordinator_impl_elect.cpp.  Leads to less
scheduling, and easier-to-follow code.
Revert "SERVER-1424 (re)smoke tag parsing and new test library, v0"

This reverts commit fac5571f67e23a1339e20e0621bab0ba2a6b7163.
SERVER-15263 Guard -D_GLIBCXX_DEBUG behind a SCons flag.

Per the message in the JIRA ticket, the _GLIBCXX_DEBUG versions of std::list<T>
type appears to have a concurrency error that leads to segfaults not related to
the code under test.
SERVER-13698: Add role and privilege info to connectionStatus output.
SERVER-15187 Add OperationContext parameter to restoreState

Storage engines might need the current OperationContext to restore their
state.

For example, BDBRecordIterator needs access to the current underlying
transaction to recreate an underlying cursor. Having the BDBRecordIterator
save a pointer to the OperationContext it was created with won't work,
because the OperationContext is destroyed and a new one created between
saveState and restoreState.
SERVER-14668 Move lock acquisition further down in receivedInsert