Fix AOL OpenID auth

[osya]

Changes for the AOL OpenID auth mostly based on the corresponding LiveJournal OpenID auth code. Three tests written (according to the LiveJournalOpenIdTest). Two of them test_login and test_failed_login passed. Test test_partial_pipeline failed. IMHO it is due to wrong response message from AOL (which contains in the server_response variable in tests). For example, OpenID namespace 2.0 should be contained in this message or openid.claimed_id should be changed to to the 'openid1_claimed_id

[omab]

@osya what's the reasoning for this change? Why drop generic openid auth with users based ones that's not backward compatible?

[osya]

@omab, the reason for this change is just existing code for AOL OpenID in the module aol.py is not worked. I began investigate it and in the end write this PR. With my changes AOL OpenID worked somehow (two of three tests written by me according to the tests for LiveJournalOpenIdTest - passed).

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.