Allow '0' as the line number in GCC errors as some tools report whole file errors as line 0.
Allow '0' as the line number in GCC errors as some tools report whole file
errors as line 0.

rhaberkorn/scintilla-mirror,rhaberkorn/scintilla-mirror,rhaberkorn/scintilla-mirror,rhaberkorn/scintilla-mirror,rhaberkorn/scintilla-mirror,rhaberkorn/scintilla-mirror,rhaberkorn/scintilla-mirror,rhaberkorn/scintilla-mirror