Updated to use the new node processor in jackalope

Updated to use the new (code merge pending) node processor in jackalope:
https://github.com/jackalope/jackalope/pull/245
seems ok to me. 
this could also become a 2.0 topic - phpcr allows to re-map namespaces on a session basis to different prefixes (to handle prefix clashes). atm we don't support that.