Revert "moved HardwareRepository submodule to src directory"

This reverts commit fea224057ff7c56964e0df5c60d6eedea16457d7.
updated INSTALL.txt
added script to run application with uwsgi
removed script to run with gunicorn
don't use bl_setup and new_frame globals anymore: now variables are attached to the application object
use environment variable for the XML files path
removed compression (doesn't work with recent Firefox ! Oh my... !)