Bunch of improvements and fixes to the admin.
Removed the assets directories from the repo.
Added a view to see and resend invites.
Fixed minor bugs in the issue pages admin section.
Added a delete button for issue posters.
Improvements to the admin page order section.
Improved the item deletion workflow.
Updated the invite confirmation/nda page.
Improved error handling and fixed bug fetching invites.
Added a link for new invites and fixed wrong form action.