Documentation cleanup: * Escape < characters in Doxygen comments as needed; * Add \code...\endcode around code examples; * Remove an incorrect use of Doxygen's \arg command.
Documentation cleanup:
* Escape < characters in Doxygen comments as needed;
* Add \code...\endcode around code examples;
* Remove an incorrect use of Doxygen's \arg command.


git-svn-id: ffe668792ed300d6c2daa1f6eba2e0aa28d7ec6c@158859 91177308-0d34-0410-b5e6-96231b3b80d8

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