Implementing setup and installation

[lzkelley]

This is a place to discuss / brainstorm how the setup script and installation of astrocats and catalogs should work in the future.

One of the first priorities should be making a test-catalog more easily runnable, and clearly show important/helpful results: see e.g. https://github.com/astrocatalogs/astrocats/issues/74#issuecomment-242333989

[guillochon]

• We need to work on minimizing the install time for Astrocats as much as possible, which probably requires purging some of the large datafiles from the history back when the main repo was storing them. It would probably be best to attempt the purge on a fork just to make sure we aren't deleting anything important.
• Installation should be possible via pip, which would remove a barrier for people who just want to dip their feet in without diving too deep into developer land. With a pip install the first point is moot, the full git history of the repo is not installed along with the package.
• Some sort of demo server would be nice to have, where people can create a sample web application from the catalog so they can get a sense of what the catalog looks like when it is deployed.