Improve patch functionality

The patch process currently requires the container to be online, and does not survive a purge of the data/ directory. This causes usability problems for customers that distribute a built container in an internal PAAS model.
Requested enhancements:

1. Ability to patch the container "offline", so customers can have a custom Maven assembly that grabs the stock build, applies patches and their configs to create a standard build that can be distributed within the organization.

2. Patch survives deletion of data/ directory.

3. Patch process allows us to purge unused artifacts. Ie.. activemq-osgi.5.8.0.redhat-60024 gets replaced by activemq-osgi.5.8.0.redhat-60033.. the -60024 artifact is deleted from system/ repo