Support mixed collections and custom templates

[dbu]

From the announcement:

Create.js now has some new collection handling features, like supporting custom templates and multiple types of items in same collection: http://bergie.iki.fi/blog/create-collections/

See and example in https://github.com/bergie/create/blob/master/examples/example-withtype.html

[dbu]

bergie also mentions this in #24 (schema export)

[dbu]

@bergie: looking at our code, i see that new items are posted as owl:Thing instead of the type they should have. its the same on demo.contentcontrol-berlin.de . is this not supposed to be the same type as the entity that was cloned?

and semi-related: we want to add new news items in a list where we just show the title. is there anything better than rendering the content along so that when we add to the collection, the entity has the content field?