SERVER-8203: replication metrics

Conflicts:
	src/mongo/base/counter.h
	src/mongo/db/namespacestring.h
	src/mongo/db/oplogreader.h
	src/mongo/db/pdfile.cpp
	src/mongo/db/prefetch.cpp
	src/mongo/db/repl.cpp
	src/mongo/db/repl/bgsync.cpp
	src/mongo/db/repl/bgsync.h
	src/mongo/db/repl/rs_sync.cpp
SERVER-7717 Removed ops section from serverStatus

Conflicts:
	src/mongo/s/mongos.vcxproj
	src/mongo/s/mongos.vcxproj.filters
	src/mongo/s/strategy_shard.cpp