Added print and export buttons to registration gridfields (+4 squashed commits)
Squashed commits:
[3297e15] Moved cancelled registrations out of toggle field
Cancelled registrations weren’t showing while inside the toggle field,
plus being able to see both gridfields together makes management easier.
[561724c] Rearranged fields on Main tab
Put the title field back where it belongs.
Moved the Metadata fields below the event specific fields
[9b22d41] Added Send Invitation button to templates

Cherry picked from @tardinha 's branch

Rearranged fields on Main tab

Put the title field back where it belongs.
Moved the Metadata fields below the event specific fields
Merge branch 'pr/cms-improvements'

Conflicts:
	code/pages/RegistrableEvent.php