Add JMdict file to the repo.

I got tired of finding and downloading it again on separate systems.
Update to improve the project structure.

I guess It could be argued whether this is actually better. The main reason
behind it is that I wanted to add support for things like mongo, and revisit
using sqlalchemy now that a few versions have come and gone.

It still lacks some Python niceties, such as package information, but it
should be an improvement moving forward.
Update to make the readme an rst file.

Mostly so github, bitbucket, etc. format it to look better.