Customer implementation. WIP.
Implement listing of customer contracts.
Part 1 of making template buttons more flexible.
Use catalyst functions to get urls.
Check for uploaded file before deleting/processing
Migrate billing templates to new button handling.
Finish migration to new button handling.

You can now define in your datatables template which buttons to
show on top and which to show per row while defining an arbitrary
action for it.

Buttons with name "Delete" pop up a confirm dialog automatically.