Provide contact email address in readme

Due to issue #21, I wanted to provide this at least as an option. This "infrastructure" is maybe a bit lighter than a mailing list. Ideally I would like to add others that have contributed significant code to this module (@coldfix and @Moredread obviously) as well but this is not necessary.

Edit: To clarify let me state it as an explicit question: does anybody else want to be added?