UP-4000: Gallery drag and drop not working with fluid 1.5.

- Updated gallery drag and drop to work in both universality and respondr.

Notes:
The `initDragAndDrop()` method call has been wrapped within a `setTimeout` to resolve a `fluid.pager` bug (i.e. [UP-4000](https://issues.jasig.org/browse/UP-4000)). When the `onModelChange` event fires the DOM contained within the `pager.container` element becomes stale. For some reason that is not yet known, the pager's internal DOM, within the `onModelChange` event, is not ready for manipulation. This is important because the `initDragAndDrop()` method needs to apply the jQuery UI Draggable plugin to the underlying list items contained within the `pager.container`. With a stale or out-of-sync DOM the list items within the gallery fail to become draggable. Wrapping this method call within a `setTimeout` with the duration set to 0 forces the `initDragAndDrop()` method to be the last JavaScript function executed, giving time for the DOM to be redrawn.

It is also important to note the `position` style definition has been dynamically added to the `body` tag to accommodate a FireFox/jQuery UI specific bug. We are using jQuery UI Draggable to drag portlets from the gallery to the portal's columns. Firefox has an issue placing the cursor correctly on the dragged element. Adding a 'position of relative' fixes this issue. A fix for this bug is schedule for jQuery UI 1.11. This fix has been added using JavaScript due to the fact that adding the position definition breaks the functionality in Chrome, Safari and IE.

StackOverflow
http://stackoverflow.com/questions/18008657/jquery-ui-draggable-1-10-3-issue-with-firefox-not-finding-cursor-center-when-win

JIRA:
https://issues.jasig.org/browse/UP-4000