- Log elapsed time per test in summary
- Command-line switch `--time-stamp` prefixes log output lines with
current time stamp (requires ts utility from Debian package _moreutils_)
Fixes#1156.
If the script is executed with an obscure path (e.g.,
'../tool/autopilot'), just taking the argv0 string fails. Therefore, the
file path is now normalized prior to the directory detection.