Allows for selecting of specific vocabularies for interests, not just all vocabularies.
Added a 'set as interest' link off nodes with future development intended. At the moment it just bumps up the interest of that node and associated terms.

may_cache was still not-set for the main menu for debugging. Was breaking the auto-learning capability

Initial commit of Interests module. May still be a bit buggy in places but it is at a functioning stage which i am happy with for the time being