Added light_angle.
Added some textures to use with knobs.
Renamed Knob.* to knobs.*

Using separate renderers for knob background and foreground.
Added rotations.*

Not using these for now.
Added repeat_s(), repeat_t(), clamp_s() and clamp_t() methods to texture.
Can rotate points. Can inset/outset rects via +/- operators.
Testing knobs.
Added new stuff.