Adds the most requested doc for the AST matchers: a reference of matchers, categorized by type and fully expanded for the context in which they can be used.
Adds the most requested doc for the AST matchers: a reference
of matchers, categorized by type and fully expanded for the
context in which they can be used.

I used a script to generate this documentation which I'll want
to be scrunitized by a code review before checking it in.



git-svn-id: ffe668792ed300d6c2daa1f6eba2e0aa28d7ec6c@162225 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/clang,apple/swift-clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,apple/swift-clang,apple/swift-clang,apple/swift-clang,apple/swift-clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,apple/swift-clang,apple/swift-clang,apple/swift-clang,llvm-mirror/clang,apple/swift-clang,llvm-mirror/clang,llvm-mirror/clang,apple/swift-clang