More Miniconda packages, more TriMet data

• Closed issues: 26 - 29
• The Miniconda image now includes pandas, geopandas, requests, psycopg2, statsmodels and seaborn.
• The PostGIS image has a new database superuser, Linux and PostgreSQL user dbsuper. Use this instead of logging in as postgres.
• The PostGIS image now includes virtualenvwrapper.
• The OpenStreetMap example now includes all TriMet public GIS data, not just the service area boundary.
• All the images now have a clone-me.bash script that clones this repository! So you can build a Docker network, clone this repository and run the examples. I'm open to suggestions for more examples as long as they use publicly-downloadable data only.