Adds vdb sequencer library to modeshape lib plugin

* In order to use the library in an OSGI environment, it is necessary to
  unpack the jar into a directory and add that to the modeshape lib
  classpath

* Version 4.1 of modeshape has a fix for this so after release, this can
  be changed back to use the jar archive as is.
Refactor Modeshape repository parent classes

* Moves Modeshape engine / repository test classes to its own utils plugin
  so that they can be shared between test plugins

* Provides framework for getting plugin specific repository configurations
  from a /data directory.
Merge pull request #36 from phantomjinx/vdb-sequencer

Vdb sequencer