add a check in parsing that some regex search was successful before accessing it

[svigerske]

We had some corrupted .out files where ipet (in rubberband) failed with some exception in the line

 data = [self.convertToFloat(misc.numericExpression.search(line, colonidx + 1).group(0))]

misc.numericExpression.search(line, colonidx + 1) returned None, and then None.group() isn't good.
The line to parse was

 Gap First Sol.   :   infinite

But I guess its the corruption of the out file that lead to an issue here now.

This PR adds a check that this isn't None.

I also had a problem to run the ipet-parse script, because logger wasn't defined in the process_one_outfiles_group() function.

[stephenjmaher]

This looks good to me.