Changed the colorAllocate and colorParse methods
Ops, forgot to make the parseColor static in the interface
Added the parseDimensions method
Added the createBlank static method
Modified the initEmpty method to use the createBlank function
Added the fill method
Modified the initEmpty method to use the new fill method
Modified the copy method to accept also resources
Added the cloneResource method and the __clone
Added the replace method
Added the wrapper tests
Fixed the modify method
Added the canvas method
Added the canvas test
Moved all the methods from the library specific to the abstract: only _modify is library dependant
Added the crop method
Added the possibility to square the crop area
Changed the exception message
Added the crop test