Populates Issue's repository from URL when not in response.

[stuglaser]

Issues created from Repository.get_issue() have their repository field set to None. This pull request manually sets the Issue's repository using the Issue's URL, when the repository has not already been set.

I've also modified the test in tests.Issue.Issue.testAttributes to verify that the repository is correctly set. The modified test does fail if I remove my changes to the library.

[jacquev6]

Thank you for your contribution!

To be honest, I'm not sure about that... Until now, PyGithub never interferes with what is returned by Github API v3. I'll think about it in the next few days.

[stuglaser]

I certainly see your point. However, it is frustrating that Issue behaves differently depending on where it's returned from.

Anyways, let me know what you decide, and thanks for the project.

[jacquev6]

You're right, I'll merge that in next release.

Later, I will try to find a more generic way to help objects know their parents (here, we do repo.get_issue(n), so we already have the repo, and we do a new request to github for this repo)