Group or filter per content type under Templates

[bjuris]

Make it possible to filter or group templates on content type.

[valdisiljuconoks]

@bjuris - any specific implementation details in mind? To do in the same "searchable" table?

[bjuris]

@valdisiljuconoks No implementation in mind, I just moved this from the readme so it was written a long time ago, but if I remember correctly we just though it would be useful when troubleshooting a content type that you somehow could see what templates could render it