Auto-correct RMG termination criterion

[alongd]

I ran a model generation with T3 with the following RMG termination criteria:

      termination_rate_ratio: 0.001
      termination_time: [60, 's']

RMG terminated once it reached the termination_rate_ratio:
At time 2.7169e-10 s, reached target termination RateRatio: 0.0009957255199092255

This is obviously not the intended behavior, since RMG terminated after less than a simulated time of a nano second only

We could add a minimal termination time to T3, and if some criterion causes it to terminate prematurely, T3 should modify that criterion and re-run RMG.