No git tag yet, testing automated packaging with version number.

Into separate files.

This requires a user who can write in /var/log. So we now create
user/group trackrdrd at pre-install, and the default config runs
with that user for the child process.

Because ActiveMQ uses std::auto_ptr, deprecated since C++11.

This leaks memory; apparently it has been an unsafe practice all
along. But support for ActiveMQ will be discontinued anyway.

and update documentation.

The "legacy" syntax is still tolerated, so a number after "track" is
skipped over. Also add a regression test in which the new syntax is
used, the old regression test is retained as a legacy test.