Fix 1473 and add vca_model_config_* to lcm charm

Changes in all operator charms:
- Optimize deps for tox environments
- Add import-order-style to flake8
- Optimize .jujuignore to reduce the size of charm artifacts
OSM LCM charm:
- Added vca_model_config_* options
Added bundle example for using a bundle
Updated the bundles and pin the new versions in the installer

Change-Id: Ic6591354fa5d1b5f43383215b2f0df13eb28ce67
Signed-off-by: David Garcia <david.garcia@canonical.com>