Fix bug 1246

Remove hardcoded hostname in dashboarder.py

Additionally, I commented out two lines in
osm_mon/collector/vnf_collectors/juju.py because flake8 was complaining
about those two not being used

Change-Id: I44c7b083fe99ee910eb4adc0da7d6a01aac5b979
Signed-off-by: David Garcia <david.garcia@canonical.com>