Properties + Versions support (inc. other patches)

Heres a patch for the API with a ton of goodies. Namely support for aspect properties (including updating them from Drupal) and versions + a bunch of other smaller patches. Also changed is the code formatting (namely tabbing) in the php cmis lib towards a more Drupalish direction.

However, as I can only test against Alfresco - functionality with other CMS require testing.

Also, instead of writing patches I could also help co-maintain this project :)