Generate legacy .dmr files on demand, remove .dmr files for core subsystems
Get rid of all .dmr files for subsystem tests
Reinstate susbsystem test controller for 7.1.2 and turn on via system
property. Also fix reading reading dmr model description for 7.1.x
Merge pull request #10 from kabir/generate-legacy-dmr-on-demand

Subsystem test framework tweaks