[TYPO3-project-4-3] extJs lightbox

[Steffen Kamper]

Hi,

i did a rewrite of Ext.ux.lightbox so it works with iframe and HTML.
With this i managed to open the help-popups in a lightbox in BE.

Precondition is #11476 which is already in corelist.

Let me know if you like to have this.

vg Steffen