Implemented "resizing" functionality

[mattleibow]

This pull request is to update jQuery to the latest stable, make 2 changes and implement the dynamic sizing:

1. fix the loading box style (centre the content and add a border) and to
2. make the filter accordion items expand to fit their contents as without this, multiple scrollbars appear.

I did format the css for editing...

Implemented 'resizable' logic into the pivotviewer:

• Pass a delegate function that will be executed when either the height or width is needed
• Moved some 'resizing' logic into css (css handles this better, but some basic j's sizing is still needed - see ResizeView in pivotviewer.js)
• preview.htm now uses resizeEnd to buffer the resizes before firing the 'refresh' method on the control

[mattleibow]

This is ready to be merged. @JacquiHand, do you think that my changes fit with the existing code?