Django1.6 compatibility
Merge pull request #760 from magopian/master

compatibility with Django1.6
Merge branch 'master' into psa2

Conflicts:
	social_auth/backends/__init__.py
	social_auth/backends/amazon.py
	social_auth/backends/browserid.py
	social_auth/backends/contrib/angel.py
	social_auth/backends/contrib/bitbucket.py
	social_auth/backends/contrib/dailymotion.py
	social_auth/backends/contrib/disqus.py
	social_auth/backends/contrib/douban.py
	social_auth/backends/contrib/dropbox.py
	social_auth/backends/contrib/foursquare.py
	social_auth/backends/contrib/github.py
	social_auth/backends/contrib/instagram.py
	social_auth/backends/contrib/jawbone.py
	social_auth/backends/contrib/linkedin.py
	social_auth/backends/contrib/live.py
	social_auth/backends/contrib/mailru.py
	social_auth/backends/contrib/mendeley.py
	social_auth/backends/contrib/mixcloud.py
	social_auth/backends/contrib/odnoklassniki.py
	social_auth/backends/contrib/orkut.py
	social_auth/backends/contrib/rdio.py
	social_auth/backends/contrib/readability.py
	social_auth/backends/contrib/skyrock.py
	social_auth/backends/contrib/soundcloud.py
	social_auth/backends/contrib/stackoverflow.py
	social_auth/backends/contrib/stocktwits.py
	social_auth/backends/contrib/trello.py
	social_auth/backends/contrib/tumblr.py
	social_auth/backends/contrib/vk.py
	social_auth/backends/contrib/weibo.py
	social_auth/backends/contrib/xing.py
	social_auth/backends/contrib/yahoo.py
	social_auth/backends/contrib/yammer.py
	social_auth/backends/contrib/yandex.py
	social_auth/backends/facebook.py
	social_auth/backends/google.py
	social_auth/backends/reddit.py
	social_auth/backends/steam.py
	social_auth/backends/twitter.py
	social_auth/backends/utils.py
	social_auth/fields.py
	social_auth/tests/client.py