Basic implentation of other hooks and XPath Rules condition.
Somewhat further.

Have a one-off and the ability to query, iterate and set values of
multiple nodes in XML in one shot.
Going to add some temporary "entity" implementation.
Fix setting of properties and flesh out comments a bit.
Adjust string.
Add "state" property to datastreams.
Add ability to specify context nodes when XPathing.
Drop reference to deleted "datastream entity controller".
Merge pull request #558 from adam-vessey/7.x-LIB-26

Additional Rules integration.