Fine grained control of curve with custom bezier field

[jeffscottward]

http://cubic-bezier.com/#.17,.67,.94,.35

I would like a bezier function to update in realtime with the option of editing it in the UI.

[jeremyckahn]

This is part of #4, but it's large enough to warrant it's own feature request - thanks for doing it. This would be a really useful addition, and I'd like to implement Ceaser for this. I'll update #4 and track the progress for this feature here instead.

[jeremyckahn]

This is implemented in v.0.3.0.