fix exports, add docs, bump version (addresses #23)

Have a look through, think we're all good.  No code changes besides exports, mostly just the docs.  I added a roadmap at the bottom with some other stuff I could do if I get a chance... chance for input before I send any more PRs :)  Also, you should `meteor admin maintainers joshowens:shareit --remove mrt`.

This is all quite ironic since I hate social and hardly ever use these networks, but need this for a site I'm working on now :)  Guess it's inevitable.