read color values from file

The program now reads color values from a file using the following
format:

<initial color>
<color 2> <steps to color 2> <wait between steps>
<color 3> <steps to color 3> <wait between steps>
...

and quits when it reaches end of file.

Thanks to Alan O'Donnell ( https://github.com/happy4crazy ) for pairing
with me on this feature!