December 30: Improvements and fixes

Fixed a bug on the Module Management page that prevented tooltips from working correctly.
Added a page that is shown to users when they try to access a page that has already been disabled.
Added the ability to delete open invoices.
Fixed various UI bugs that made spacing look bad in text-heavy areas.
Fixed a bug where an infinite spinner is shown when trying to connect a new custom domain.
Fixed a bug where the Create button is not shown on the User details page (Invoices tab).