show --help in emcc even if there are other args

emcc

@@ -110,7 +110,7 @@ while response_file:
       sys.argv[index:index+1] = extra_args
       break
 
-if len(sys.argv) == 1 or sys.argv[1] == '--help':
+if len(sys.argv) == 1 or '--help' in sys.argv:
   this = os.path.basename('em++' if os.environ.get('EMMAKEN_CXX') else 'emcc')
 
   print '''%s [options] file...