Support remote name configuration

[rcisterna]

Existing Problem
Currently, change only support a remote named origin. So, if I have only one remote with a different name, it fails with an exit code 1, and a message saying remote origin url isn't set for this repo.

First Solution
It would be nice if, instead, change worked something like this:

• If I have only one remote, change should use that one.
• If I have more than one remote, try to use origin or fail just the way it fails now.
• Allow to configure the name of the remote for all my repos (with an environment variable like CHANGE_REMOTE_NAME for example), or a .env like file (that could be called .change) to select the name of preferred remote.

Alternative Solutions
I actually don't have any more ideas.

Further Explaination

[rcisterna]

If you are open to it, I can help you with this 😁.

[adamtabrams]

I've created a PR that attempts to support this, but with a different strategy. Instead of adding logic to handle different remotes (which I couldn't find a robust way to parse) or adding a config file, this just uses urls instead (as supplied by git ls-remote --get-url).

@rcisterna I'm not sure if this use case is still relevant to you. But if it is, would you be willing to test if these code changes fix the issue?

[rcisterna]

Hi @adamtabrams! It's currently not relevant to me, but it will be a pleasure to help you test the changes.

[adamtabrams]

Does the version here behave as you expect for branches with multiple remotes? Also when there's only one remote, but it isn't named origin?