Tweak the interface for analyzing the CF conventions for a name

to take a FunctionDecl* instead of an llvm::StringRef.  Eventually
we might push more logic in there, like using slightly different
conventions for C++ methods.

Also, fix a bug where 'copy' and 'create' were being caught in 
non-camel-cased strings.  We want copyFoo and CopyFoo and XCopy
but not Xcopy or xcopy.

llvm-svn: 140911