Add composer.lock, remove gumph

No need for Contributing file, people know how to send pull requests
and I don't have a special repo or anything. Add the composer.lock
as well so people definitely get working versions of packages.
Set version and update readme

It's about time I got round to sorting the readme, so now it has
a basic overview of what the project is about, and basic install
instructions so people can get started. All untested of course.
Merge branch 'release/0.1' into develop