Update CHANGES.txt for 0.4 (still missing campaul's latest)
Fix z-index on picker and options
literally.css -> literallycanvas.scss
Merge pull request #165 from irskep/tweaks

CSS tweaks (rename literally.css to literallycanvas.scss, fix z-index issues)
Minimum height
Merge pull request #166 from irskep/tweaks

Minimum height
Use requestAnimationFrame when it's available
Merge pull request #168 from campaul/request_animation_frame

Use requestAnimationFrame when it's available
setDefaultImageURLPrefix
Merge pull request #169 from irskep/default-prefix

setDefaultImageURLPrefix
Add LC.setDefaultImageURLPrefix() to CHANGES.txt
Merge pull request #161 from irskep/changes-txt

Update CHANGES.txt for 0.4
Every shape gets a GUID
LinePath and ErasedLinePath store data much more efficiently
saveShape() can save shapes below other shapes, and avoid triggering the event
shapeSave event includes afterShapeId