Render modal content outside most of the DOM

To remove interference from other css styling. As it’s absolutely positioned it doesn’t matter where in the DOM it is.
A factory to build a complete claim model
Display outstanding claims and approve/deny them

If user is admin then they can see all claims not just
ones against datasets they own.
Send emails for notifying of claims

Currently only certificate@theodi.org will be notified of claims. Unset Claim::DELIVERY_ADMIN_OVERRIDE to change this