Update property javadoc
Rename snap-to-drag to dragsnap in css
Do not allow user to resize to oblivion

Simply stop registering the resize if it gets too small
Tidy up now divorced curve code
Tighten up logic for curve activation

If you activate a curve before putting it on the canvas
setting it as draggable has no effect.

Perhaps the curve should be the one controlling this,
though
Remove extraneous resize hint
Tidy up CSS file
Slightly refactor curve placement logic