Merge pull request #705 from edx/renzo/bump-auth-backends

Bump auth-backends and remove PSA pin

requirements/base.txt

@@ -13,7 +13,7 @@ django-waffle==0.10.1
 djangorestframework==3.2.3
 djangorestframework-jwt==1.8.0
 drf-extensions==0.2.8
-edx-auth-backends==0.2.1
+edx-auth-backends==0.2.3
 edx-django-sites-extensions==1.0.0
 edx-drf-extensions==0.4.1
 edx-ecommerce-worker==0.3.3
@@ -26,9 +26,6 @@ paypalrestsdk==1.11.5
 premailer==2.9.2
 pycountry==1.18
 python-dateutil==2.4.2
-# The following pin is needed for https://github.com/omab/python-social-auth/pull/897
-# we can remove once merged.
-python-social-auth==0.2.14
 pytz==2015.7
 requests==2.9.1
 suds==0.4