GUI cosmetics

IMHO it would be nice to have 1 px top margin around [X] [_] in the corner of main window in fullscreen like in dialog boxes. Also [X] could be [X] with the same size as in dialogs. Now it reminds me window from windows (sticky to border with close bigger than anything) that i’m happy to quit…)

RENOISE V3.0.0 b3 OSX 10.9.1