Stray cleanup, minor.
New: RKDespeckle.

- despeckle.js refactored into object oriented plugin style
- split 'init' out into many functions, worked on limiting the scope of variables, since before, everything was in one giant code block.
  - Many of the variables are still scoped to the entire file, but it's appropriate for most of them.  I didn't want to change much functionality with this commit.
- changed a lot of variable names
- the slider is now fully external (defined now in the html file)
- the two main viewers (thumbnail and viewPort canvases,) are now created by RKDespeckle instead of in the html, so the user of the plugin only needs to create one parent element.
- reorganised the signatures of binarise() and despeckle().  They now access the blue view box instead of taking extra arguments.

Refs #179