RepositoryService: implement CreateRepositoryFromURL
This is the main method behind various imports. It seems to be readily applicable to Mercurial
Surprinsingly, it is synchronous, called from the Rails app with a "long timeout" that is set to 6 hours for Rails background jobs (see Gitlab::GitalyClient.long_timeout
). This property can cause problems with our request handling, since we're using a prefork model with a pool of fixed size, but that shouldn't be considered part of this issue (and should become a follow-up if still current at the time of implementation)