Form Editor: Allow events to create form templates

[knomepasi]

Form templates may or may not be editable once used. The main benefit from this would be to force some level of consistency within forms.

[japsu]

Currently ordinary surveys can be initialized as clones of existing surveys (that the author has visibility into). This is possible across purpose, events and apps. I'm thinking might this actually fulfil the need for form templates?

Program forms (offer / accept invite) currently do not have this functionality, but adding them would not be a significant effort as the backend code needs very little change to accommodate this.

What I've been thinking, however, is that when a program offer form is initialized from scratch, it should probably have the title and description fields by default. It's not like program managers would often forget those fields, and the help texts and even titles of those fields may vary from event to event and even from form to form, but the fields generally need to be present on every program offer form.