SERVER-7028 Move complex initialization (that may trigger page fault exceptions) out of ReplSetConfig and ReplSet constructors.

Conflicts:
	src/mongo/db/repl/replset_commands.cpp
	src/mongo/db/repl/rs.cpp
	src/mongo/db/repl/rs_config.cpp
	src/mongo/db/repl/rs_config.h
	src/mongo/db/repl/rs_initiate.cpp
	src/mongo/dbtests/replsettests.cpp

As part of this cherry-pick, 7ba171df needs to be backported as well
SERVER-7367 Don't go through the network to pick up a local config

Conflicts:
	src/mongo/db/repl/rs_config.cpp
refs #567, fix some missed conflicts