Add check for working/buggy gen-patt version

The ITU STL tool gen-patt is unfortunately buggy in the most recent version. See https://github.com/openitu/STL/issues/161 for details.

I would propose to add a check for the working gen-patt version before creating the sta-file and calling gen-patt. It could consist of:

1. Create temporary directory
2. Run gen-patt from within the temporary directory, e.g. gen-patt -tailstat -fer -g192 -gamma 0 -rate 0.05 -tol 0.001 -reset -n 100 ep.g192
3. Check, whether gen-patt creates a sta file in the temporary directory: If yes, everything is in order, proceed; if no (i.e. the file has a different name), abort with a proper error message, clarifying that a non-working version of gen-patt was detected
4. Clean-up temporary directory