fix(autogrow): refining autogrow_cols behavior and grid width issues
fix(resize.stop): Call resize.stop at the latest possible moment

Previously the resize.stop callback was being called before the widget
had reached the end size that Gridster would make it (the widget grows
to match the placeholder size after releasing the drag)

This change pushes the resize.stop callback to the last possible moment
where the size of the widget the callback receives is more likely to be
correct.

Signed-off-by: ciaranj <ciaranj@gmail.com>

Conflicts:
	src/jquery.gridster.js
feat(draggable): Add toggle draggable method.
Release v0.5.0