SERVER-14062 Move most non-global curop access through OperationContext
SERVER-13575 log rollback operation progress every 10 seconds

also stop double counting deletes from non-capped collections
SERVER-13960 bug fixes for OR with inexact predicates
Revert "SERVER-13627 disallow 0-vote arbiters"

This reverts commit 07838d04bece908d12d7f0ded46a0a75ff77608f.
Merge branch 'master' of github.com:mongodb/mongo
Merge branch 'master' of github.com:huadianz/mongo