Change to the root directory before executing (stops Mumble ICE file errors)

This was causing the SSO job to fail, thanks for psu3d0 for pointing it out.

run-cron.py

@@ -5,6 +5,7 @@ import os
 
 # Activate the virtualenv
 path = os.path.dirname(os.path.abspath( __file__ ))
+os.chdir(path)
 activate_this = os.path.join(path, 'env/bin/activate_this.py')
 execfile(activate_this, dict(__file__=activate_this))