Fix broken img

_data/course.yml

@@ -58,7 +58,7 @@ signups:
    twitter: angela_brown
    github_username: dreamingwombat
  - name: Nicole McGee
-   image: https://pbs.twimg.com/profile_images/525689865321447424/8QDwDPKh.jpeg
+   image: https://pbs.twimg.com/profile_images/530473525945978880/LYMJ07-U_400x400.jpeg
    twitter: nicolejam
  - name: Robert Morris
    image: http://s4.postimg.org/s0w975fp9/coalminer2.png