Document model/API

Documents can be represented as a certain set of nodes (or subtree or nodes) in the JCR repository. From a frontend perspective, exactly how the document model maps to the JCR should not be (too) relevant. Ideally the frontend uses some interface which is independent of the mapping on the JCR.

(Just emptying the contents of my brain in Jira.... I have no idea how feasible this is but this is the time to decide over this)