__init__(): simplify, use tuple as key to __byrgb, lowercase __byname key.
__init__(): simplify, use tuple as key to __byrgb, lowercase __byname key.

find_byrgb(): Changed name, interface (takes a tuple), and return
value

find_byname(): lowercase color name

sk-/python2.7-type-annotator,sk-/python2.7-type-annotator,sk-/python2.7-type-annotator