#35 (Util::operaReplacer method modified: not to allow null values and to erase last decimal zero digit(s). Added number checks on inputs of canvas width & height.) Serialization fails on Opera 11.15
#35 (CanvasProps comments modified: String -> back to Number in setters. RegExps modified in operaReplacer method: 'g' key removed.) Serialization fails on Opera 11.15
#35 (added some comments) Serialization fails on Opera 11.15