Blender Git Loki

Beware, coded between 10 phone calls and 20 sudden surprises, but I still
hope it's somehow usable :-)

Colourpicker update:
-------------------

1) Converted numbuts to sliders and made the colourpicker wider. Sliders
are more useful for something like RGB and HSV because they're fixed
range values

2) Added a hex button for entering HTML-like color (#RRGGBB, can be
entered both with and without the hash sign).

This should completely replace the former strange NKEY functionality
in buttonswindows, and even add hex support for buttons which didn't
have it before.

Please test thoroughly, I never coded something in a hurry like this.

There are small rounding errors still... Maybe someone finds the
reason? :)