Issue 1459 avatar functional tests

This depends on #1512 (only the last commit is for this PR). This mocks out some client side functionality, like capturing webcam images and selecting a file from the filesystem.

Fixes #1459.
Fixes #1494.
We can check the changed value of `top` with `getComputedStyle`?
![image](https://cloud.githubusercontent.com/assets/128755/3885710/65f06a78-21c9-11e4-81f9-016022019011.png)