public bool parse (string spec)
Fill in the fields of a color from a string specification. The string can either one of a large set of
standard names. (Taken from the X11 rgb.txt file), or it can be a hex value in the form '#rgb' '#rrggbb'
'#rrrgggbbb' or '#rrrrggggbbbb' where 'r', 'g' and 'b' are hex digits of the red, green, and blue components of the
color, respectively. (White in the four forms is '#fff' '#ffffff' '#fffffffff' and '#ffffffffffff')