cljr add project dependency
Easily add new project dependencies. Completing read among artifacts
from clojars, and a selection from maven central, followed by a
completing read of available versions, insertion into project.clj and hotloading into the repl.
When this function is called with a prefix the artifact cache is invalidated and updated. This happens synchronously.
The variable cljr--hotload-dependencies defaults to true and
determines if new dependencies should be hotloaded or not.
