RJ TextEd's support for Objective C and Objective C++

[bprlhe]

Syntax highlighting for Objective C (.m) and Objective C++ (.mm) are not in good shape.

.m file has limited syntax highlighting, and .mm file has no syntax highlighting at all.

Both Objective C and Objective C++ share the same .h extension for header files with C/C++.

The editor can't detect if the .h file is in Objective C or Objective C++ instead of normal C/C++.