Recognize .C files as C++ source
Pygments currently recognizes files ending in ('.cpp', '.hpp', '.c++', '.h++', '.cc', '.hh', '.cxx', '.hxx') as C++ source.
Please add '.C' (capital C) and '.H' to this list.
These are additional standard file extensions recognized by gcc as denoting C++ source. For example, see here: http://gcc.gnu.org/onlinedocs/gcc/Invoking-G_002b_002b.html