#304 tilegtk - locale and decimal seperator

[Lasse Bombien]

I just found tilegtk and I like it very much, thank you. However, as soon as the theme was loaded, geometrical (?) calculations when drawing the GUI failed because of kommas in floating point numbers. This is locale related (komma is the decimal separator in German). I can avoid this by switching to another locale (e.g. C), but that's not what I want. Thanks in advance.