Update logo and login and remove deprecated files

![modx_cmf_manager_login](https://cloud.githubusercontent.com/assets/234237/3664790/1d994bc6-11e0-11e4-9a93-585c3d23eb9b.png)

![help___modx_revolution](https://cloud.githubusercontent.com/assets/234237/3664819/3f0287c8-11e0-11e4-9cc3-f2c84f7fa1b9.png)