ColorScheme constructor with a filename outside parent.dataPath

[acarreras]

Hi,
To reuse code and data sometimes it's useful to have .xml files outside the sketch dataPath folder.
It would be interesting to be able to use ColorScheme with an .xml outside the Processing sketch data folder. However the constructor forces the .xml to be there.
It would be nice to add the option and let coders choose the filename and it's path.