Unify Options.td and CC1Options.td, in a first step towards unifying the serialization logic in Frontend and Driver.

Reviewed by Eric, Doug and Chandler, and here: http://llvm.org/reviews/r/7/



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@155916 91177308-0d34-0410-b5e6-96231b3b80d8