Par-Test includes log in transcript of failed exec

The previous behavior was that the Failure is generated
before the log is appended to the transcript.

That meant that the summary transcripts wouldn't include
the log file. Luckily, the transcript would say something
like "jvm > showFail-run.log".
Merge pull request #2512 from som-snytt/issue/partest-exec-log

Par-Test includes log in transcript of failed exec