fixed crash issues, during opening SGFs, preparation for other improvements
improved parser, simplified MoveEvent management, now MoveEvents(previously MovePlayed) are dealt with always as MoveEvent Objects and never as NSArrays converted into objects
also adds comment to MoveEvent
comments are now displayed
Merge branch 'master' into improvements

Conflicts:
	NadohsSgfReader/goAppDelegate.m
Merge pull request #4 from Nadohs/improvements

Improvements
fix conflicts
fix crashes at start with empty board no sgf loaded, trying to arrow through
fixed crash when no SGF loaded
Merge pull request #5 from Nadohs/improvements

Improvements