Updated Install and Recover with TFTP guide for Ubiquiti.

Per issue #239.

Updated the "blinking lights" images, and added new ones. Old support images updated as well. Reverted to an old PDF.

@dismantl - Can you take a look and let me know if this fixes the issue?

The PDF will need to be updated with the new light sequence, but that will happen later. I will create a new issue for that.

@critzo @natmey - Can you take a look at this after @dismantl says okay, and merge when ready? Thanks.