sajolida discovered a bug in the way some of our torifying wrappers
handle passed-through arguments. This branch fixes that bug, and adds
automated tests for some of it.
Note that one of these wrappers (connect-socks) affects e.g.
Git cloning over SSH, which should be tested when reviewing #8680 too,
so I've assigned this new merge request to bertagaz (who took #8680
a week ago) for review. bertagaz, if that's not OK with you, please
de-assign yourself.