Update README: app and app-tools 0.1.11-SNAPSHOT are available in Clojars

Since [`[app "0.1.11-SNAPSHOT"]`](https://clojars.org/io.pedestal/pedestal.app/versions/0.1.11-SNAPSHOT) and [`[app-tools "0.1.11-SNAPSHOT"]`](https://clojars.org/io.pedestal/pedestal.app-tools/versions/0.1.11-SNAPSHOT) are both available in Clojars I would suggest removing this section of the README to simplify getting started for new readers.