Provide Dockerfile

[kuanb]

Note, relates to Issue: #12

Dockerfile provides a clean, consistent environment for development and execution of library.

Making it available if desired. :)

[kuanb]

Not to rope @jalessio into this 😃 , but v helpful critique of this Dockerfile. Will revisit and make edits (again, just should anyone find this of use):

1. "too many layers… consolidate all those multiline commands into a single RUN like you have for the GEO libraries. Also, running apt-get update and apt-get install in separate RUN commands is a bit of an anti-pattern for a Dockerfile"

2. "also, I think you’re doing the “cleanup” step too early in the process — you should so that at the end, since the apt commands you run for GEOS will just re-populate /var/lib/apt"