RandomNumberService unscheduled fix

Fix the random number service so that it will
not trigger unscheduled execution of the producer
that saves the random states when it tries to read
the random states. It will now always skip the
current process when getting it.
Merge pull request #1598 from wddgit/fixPostRead

Multithreaded framework -- RandomNumberService unscheduled fix
Merge remote-tracking branch 'origin/CMSSW_7_0_X' into CMSSW_7_0_X