Some progress made on the akonadi model

* Created a CollectionAndItemModel
* Removed dummy books from the akonadi resource.
* Let KJotsPage create a page by reading a file.
* Removed some models that didn't work.

Now the plasmoid displays a model of books and pages, but books can not be nested.

Also, I need to figure out a way to remove the unwanted collections from other resources, and make the Bookshelf the root item.

Probably need to be much smarter about the signals and slots for jobs and model changes to solve these issues.