Updated the installation scripts and wiki to reflect the new location of the dfall-system repository

Purged the code of all occurances of the terminology teacher. This was replaced by either master or by System Config GUI

Adjusted installation script so that it add comments to the .bashrc file and to add a change directory allias

Updated install scripts for the new ROS packages key. Also added partial install script to make Rasp Pi installation easier

Added install git command to installation scripts. The installation script is tested and working for a fresh install of ubuntu 18.04

Updated installation script to match current naming conventions. And updated installation wiki page to match.

Updated wiki and install folders for the change from pps_ws to dfall_ws, and from d_fall_pps to dfall_pkg