Add a script for doing proxy recordings in non-gui mode

**Lars H** ([Bug 60335](https://bz.apache.org/bugzilla//show_bug.cgi?id=60335&redirect=false)):
I would like to be able to record a test plan using the proxy recorder without using the gui.

My main use case would be in a CI pipeline, where an automated test (executed using some other tool) could trigger the interaction with the system under test, and automatically record a user session i jmeter. The recorded test plan would be used to validate that requests have not changed between runs, and serve as a base for updated load tests.

Now that https://github.com/apache/jmeter/issues/3491 has been fixed, it should be fairly easy to solve. I think it could be done in a fashion similar to bin/mirror-server.sh.

The script could terminate and write the test plan on CTRL+C/SIGINT.

In order to facilitate things like variable substitution & response logging, I think it would make sense to be able to provide a test plan as input to the script (the script would then load this file before starting the recording)

OS: All