3060 Don't error when given https URLs for parent & external works

[sarken]

https://code.google.com/p/otwarchive/issues/detail?id=3060

For internal works, we just want to see if it's a work on the archiveofourown.org domain (APP_HOST) rather than checking if it's on http://archiveofourown.org (APP_URL).

For external works, we want to turn the https:// into http:// automatically

[houndci-bot]

Trailing whitespace detected.

[coveralls]

Coverage decreased (-0.67%) to 73.18% when pulling a4518be on sarken:issue_3060 into 4bb9f9a on otwcode:master.

[coveralls]

Coverage decreased (-0.67%) to 73.18% when pulling a4518be on sarken:issue_3060 into 4bb9f9a on otwcode:master.

[coveralls]

Coverage decreased (-0.15%) to 73.71% when pulling a4518be on sarken:issue_3060 into 4bb9f9a on otwcode:master.

[coveralls]

Coverage increased (+0.01%) to 73.86% when pulling 118698c on sarken:issue_3060 into 4bb9f9a on otwcode:master.

[zz9pzza]

In a more perfect world we would have a list of url's that we can be reached at. Or we would fetch the url and see if it redirected to APP_HOST