Move the README to README.md so Gerrit can render it; currently
Gerrit only renders files named exactly "README.md" (for example at
https://go.googlesource.com/go).
Add more links to the README explaining how to file issues,
how to submit code changes, where to download the code to and
how to get it. Hopefully this should help people who go to
https://go.googlesource.com/image or https://github.com/golang/image
figure out how to get started with development.
Change-Id: I390d4bd84c9fd7d0bd3f3f56f63ea8482d03a725
Reviewed-on: https://go-review.googlesource.com/49830
Reviewed-by: Kevin Burke <kev@inburke.com>
