Allow custom (shorter) timeouts

[MCOfficer]

I recently recommended apt-spy2 for CI environments, to ensure apt-get install does not fail, ever. The usecase is just to find a working mirror, quickly.

Trying it out, i noticed that apt-spy2 check stalls for about 2 minutes because a single mirror in the list is unreachable. Some of our CI runs complete in less time, so it would be cool if one could speed up apt-spy2 check. In my opinion, the best way to do so would be a custom timeout - set it to 3s and you get a working mirror almost immediately.

Edit: this probably applies to all other subcommands as well.

[till]

@MCOfficer let me know if you want to start a PR, happy to help.

[MCOfficer]

@MCOfficer let me know if you want to start a PR, happy to help.

I'm not familiar with ruby and don't have time to get into it, sorry. Here's hoping someone else picks it up.

[till]

@MCOfficer Could be as simple as this: https://stackoverflow.com/a/26066923 (in the downloader class).