Updated widgets

Updated widgets in colorwidgets.py:

• More uniform API
• Buttons can be toggled
• Buttons can have conditions (be grayed out)
  In colorsphere.py, made Home button move color sphere to original position.

Extended package with widgets

The purpose with this release is to prepare for creating interactive user interfaces with the color sphere.

• Extended the package with useful widgets for user interfaces.
• Modified the color sphere to use better gamma for smoother surface.
• Adjusted controls by adding arrows for rotating (and no control-modifier needed on scroll wheel when going inside sphere).

First release, second attempt

Maybe gets it right now

First release attempt

Just checking - will probably fail