Re-organize code for ease of use

Added a "SquiggleDraw" directory with the sketch and a "data" folder.
This prevents Processing from requesting that you move the sketch into
a like-named folder. (And, thus, prevents the situation where the
Carson image cannot be found because it wasn't moved along with the
sketch.)

Added note to the readme about ControlP5 dependency.

Both of these changes are made in response to multiple instances
reported to us of people running into these issues.

README.md

@@ -6,6 +6,9 @@ You can use the saved SVG file to print from Inkscape/AI/etc, draw with a pen on
 
 This is code for Processing (http://processing.org)
 
+Additional dependency: Download and install controlP5 in your processing libraries directory. ( http://www.sojamo.de/libraries/controlP5/ )
+
+
 Features: 
 * Simple UI to load/save images, adjust parameters related to the sine waves, and basic image adjustements
 * Saved SVG is larger than original image for detail