Fix an OAuthServer issue where an attacker could make a link function over HTTP when it should be HTTPS-only

Summary:
Two behavioral changes:

• If the redirect URI for an application is "https", require HTTPS always.
• According to my reading of http://tools.ietf.org/html/draft-ietf-oauth-v2-23#section-3.1.2 we need to check both names and values for parameters. Add value checking. I think this makes more sense in general? No one uses this, soooo...

iiam

Test Plan: This has good coverage already; added some tests for the new cases.

Reviewers: vrana

Reviewed By: vrana

CC: cbg, aran, btrahan

Differential Revision: https://secure.phabricator.com/D5022