Fix login links.
Fix about/me.html login links.
Change from "Bad request" to "Forbidden" of the expected result of test_github_associate and test_twitter_associate.
Add PlatformOAuth1 class a Platform class with support for OAuth1.
Twitter login with OAuth1.
Add PlatformOAuth2 class a Platform class with support for OAuth2.
Github login with OAuth2.
Adapt OAuth1 to Bitbucket.
Bitbucket login with OAuth1.
Fix links to connect accounts.
Fix action to connect accounts.