Allowed Emscripten to recognize and compile .m and .mm files
(Objective-C and Objective-C++, respectively)
show --help in emcc even if there are other args
Simplified code by using a tuple in combination with `endsWith`.
Merge pull request #1203 from michaeljbishop/objc-support

Allow Emscripten to recognize and compile .m and .mm files
auto-export malloc, needed by file packager
handle globals with no value and no zeroinit