VID-488 Base functionality working

Now need to get UX and UI working better
add classes to some history page elements, implement ajax workflow for lvs history page
cache href string instead of location object
VID-488 Fix up header and add back/forth links
updated from code review comments
removed unused function
fix undefined url var
VID-488 Reuse Undo messages, remove inadvertant quotes
VID-488 Several changes recommended by code review
VID-488 Remove unused message keys
Merge pull request #1227 from Wikia/LicensedVideoSwap-VID-488-HistoryPage

Licensed video swap vid 488 history page