Compute elapsed time for verifying a goal (in seconds).

See merge request laiser/caisar!5

Rework Marabou support in terms of satisfiability.

See merge request laiser/caisar!4

Do not remove temporary files on verbose mode

Closes #4

See merge request laiser/caisar!3

Unify solver output to print just the result of verification.

Closes #1

See merge request malberti/caisar!2

- Solver output is redirected to a temporary file.
- Result is extracted by means of regexps from such temporary file.

Modification of model.ml and model.mli files (actually recognize nnet format)

Closes #3

See merge request malberti/caisar!1

- DIR must be set with absolute paths, otherwise an error is displayed.
- Create, write and close the configuration file only if no failure happens
  during the detection process (note that empty detection is fine).