Fully automate regression testing

[DeadParrot]

The current regression testing scripts are meant to be used when QSS, the OCT, or Buildings Library are updated. They should evolve to be fully automated so that regressions can be readily identified.

Some of the obstacles to full automation are:

• The FMU build options may need to change between OCT releases, for example to test if directional derivative support is working when it didn't previously.
• Metrics for acceptable solution differences for different variables are not easily set.
• Some models may have long run times and using a shorter simulation time span may miss regressions.

[DeadParrot]

A first pass at support for this was pushed in eab329832b26f44dfb557734d755c17cb9199be6.

I'll leave this open for now pending near-term suggestions/refinements and put it in the Future Milestone for possible further refinement.