feat(docs): add more docs!

[valorkin]

@ocombe
okay
first thing: more docs, maybe with a project demo
second thing: it would be nice to have some kind of "init my lib" cli command, to start a new library with everything configured just the way it works

in the "more docs" sections, let people know how their lib will be consumed (is it import "mylib" or import "mylib/mylib", or how do you configure systemjs? where does it export the actual bundles? what kind of bundles? is it umd?)****