Break off declaration of Analysis enum into Analyses.def. The driver options in

clang.cpp now #include these definitions to create the command line options, and
AnalysisConsumer #includes this file to generate the switch statement to create
actions.

Renamed -check-objc-methodsigs to -warn-objc-methodsigs.

The "missing -dealloc" check is now optional: -warn-objc-missing-dealloc

llvm-svn: 53575