Switch cas repo to K-State's

- it werks on my machine
- let me know if anything breaks but I have tested users and it is a non-issue

requirements.txt

@@ -4,7 +4,7 @@ django-piwik==0.1
 django-qrcode==0.3
 django-simple-captcha==0.5.1
 flake8==2.5.1
-git+https://github.com/the-ben-waters/django-cas.git
+git+https://github.com/kstateome/django-cas.git
 gunicorn==19.4.5
 hashids==1.1.0
 mccabe==0.3.1