arrow

ARROW-2486: [C++/Python] Provide a Docker image that contains all dependencies for development

Open items
- [x] Why is `py.test pyarrow` failing on plasma deps when script follows [docs](https://arrow.apache.org/docs/python/development.html#developing-on-linux-and-macos)?
- [x] Should `/script/*.sh` use the same code as developer docs to avoid denormalization?
- [x] Move docker image to Apache registry?
- [x] Multiple container strategy possible, but overly complex. Requires exposing volume on one container as a mount point for a second container. Only speeds up user's first build.
- [x] Are gcc/g++ 4.8 the ideal versions?
- [x] Unit tests needed?
- [x] Update README per resolution of above

Author: Aneesh Karve <aneesh.karve@gmail.com>

Closes #2016 from akarve/master and squashes the following commits:

5aec17a8 <Aneesh Karve> final PR feedback; README indendtation