[cpp] unexpected indentation after a macro followed by a block

[takamori]

Repros with the following code; pressing Enter after the closing brace results in indentation:

#include <iostream>
#include "mystuff/util.h"
FOO() {
}

This doesn't occur in the base C++ mode w/ smartIndent and other settings enabled.

[marijnh]

There were two issues causing this, the first is handled in attached patch, but the second is that macro names are only recognized when they have an underscore in them, as per discussion in #94. We can change that, but it might lead to false positives.