SERVER-15178 Native SHA-1 and HMAC algorithm support
SERVER-15249 move QuorumCheck class declaration to header file for testing
SERVER-15249 test QuorumChecker's ScatterGatherAlgorithm
SERVER-15398 test HeartbeatResponse from higher priority nodes causing stepdown
SERVER-15509 test additional config initialization and validation failure cases
SERVER-15510 test validateConfigForReconfig/Initiate/HeartbeatReconfig/StartUp
Merge remote-tracking branch 'upstream/master'