Try again to fix the close request script.

Fixes bug #1012310

Seems github won't let you request an issue if issues are disabled
on a repo. So attempt to get around this by creating an Issue object
derived from a pull requests URL. Then comment on this issue object.

Change-Id: If64640ebc1d86d86360e5657f4245541620fcebb
diff --git a/close_pull_requests.py b/close_pull_requests.py
index 245bbcc..202d2eb 100755
--- a/close_pull_requests.py
+++ b/close_pull_requests.py
@@ -89,6 +89,7 @@
     pull_requests = repo.get_pulls("open")
     for req in pull_requests:
         vars = dict(project=project)
-        issue = repo.get_issue(req.number)
+        issue_data = {"url": repo.url + "/issues/" + str(req.number)}
+        issue = github.Issue.Issue(req._requester, issue_data, completed = True)
         issue.create_comment(MESSAGE % vars)
         req.edit(state = "closed")