LPS-44595 - Users shouldn't be able to drag portlets to non-customizable columns

Hey @natecavanaugh,

Attached is an update for http://issues.liferay.com/browse/LPS-44595.

NOTE: We need the ```:not()``` filter for the dragNodes property because now all nodes are draggable and we should not be able to drag nodes in a non customizable column.

Please let me know if you have any questions.  Thanks!