URLWithString:relativeToURL: > URLByAppendingPathComponent:

UIApplication gets rustled at the former, works fine with the latter. :trollface:?
Ugh, just use +URLWithString: instead

Query strings get all weird with -URLByAppendingPathComponent:
Merge pull request #125 from octokit/fix-open-url-ios

Get rid of URLWithString:relativeToURL: