Computation times

00:00.000 total execution time for 7 files from examples/iis:

Example	Time	Mem (MB)
Copt IIS (iis_copt.py)	00:00.000	0.0
CPLEX IIS (iis_cplex.py)	00:00.000	0.0
CP Optimizer IIS (iis_cplexcp.py)	00:00.000	0.0
Gurobi IIS (iis_gurobi.py)	00:00.000	0.0
OR-Tools IIS (iis_ortools.py)	00:00.000	0.0
Pyomo IIS (iis_pyomo.py)	00:00.000	0.0
SCIP IIS (iis_scip.py)	00:00.000	0.0