Ability to add content to elements selected within a skeleton

[madmatt]

Could we have the ability to define custom content within a skeleton? So instead of creating a new SkeletonPart object, you just create an Element which lets you add all the content you normally could with that Element, and when it's added to an actual page, a full deep-clone is performed?

This would let you use skeletons to define both a structure, and a bunch of default content - which could differ from one skeleton to the next. This would be especially useful for laying out different pages in a consistent way, that quickly shows to CMS editors what content should look like. Perhaps an optional selection between 'Copy structure without content', or 'Copy structure and content' options when adding a skeleton to a page.

Happy to PR this if you like - I think dropping the SkeletonPart and building on top of the existing Element in that case is the best option. Presumably only allowing an Element to be associated either with a Skeleton or SiteTree object to prevent confusion. Thoughts welcome on how best to structure this.

[pitchandtone]

That makes sense to me @madmatt, it would provide a nice balance between block sets and more abstract content design.

If you set AvailableGlobally to false on the Element, then the elements won't be able to be linked virtually either.