Added hint to update web interface shell script for how to add write access to the group for all files in the /var/www/html folder

Web interface now working for launching both the master and agent. VERY IMPORTANT is the command added to the web interface install script that the www-data user must be added to the plugdev group so that nodes launched by the web interface have permission to access the CrazyRadio USB dongle

Added first attempt at a web interface. This was used for the IFAC video, but needs more work to be used of the home version of the pands