Grepable output of final time.
Easily greppable tags.
Merge pull request #169 from AdrienChampion/feature_output-final-time

Grepable output of final time.
Base and step now add valid props as invariants.
Removing obsolete update_trans_sys_tsugi in event.
Merge pull request #171 from AdrienChampion/bugfix_kind-valids-as-invariants

Bugfix kind valids as invariants
Better support for CVC4

- Cast integer literals to reals if returned in a model for a
  real-valued term or variable
- Fail if using precise quantifier elimination or switching to it
Merge pull request #172 from chsticksel/develop

Better support for CVC4
Warn if using inductive step without BMC
Merge pull request #173 from chsticksel/develop

Warn if using inductive step without BMC