no-jira: enhance course db to list of used categories, and accept repository entry keys as course id

OO-973: implements a strict check on ownership of the resources in the query, return only courses where the author is in the owner security group

OO-972: make WebDAV work with Mac OS X 10.9, replace the lock token generator, more code to mimic Apache 2

no-jira: better catch the IllegalArgumentException to send a user friendly response instead of a stack trace

OO-962: fix the RS, enhance the method to accept an array of restricted types, expand and update the unit tests