Namespace support in servicemix-drools

We want to support the evaluation of xpath expressions with namespace when writing the
rule conditions on drl file

To do this we want to introduce support similar to the eip components where namespace context can
be specified.

Another thing we want to indroduce is to enable to make database checks in the drl file.
To do this we can use a DbHelper object and add a method to extract data from xpath in org.servicemix.drools.model.Message