Bump clojure dependency to 1.5.1
Use vars in hooks per leiningen documentation

Plugin guide recommends using vars instead of functions so that double-
wrapping can be avoided.

https://github.com/technomancy/leiningen/blob/stable/doc/PLUGINS.md
Fix reference to eval-in-project
Let client app manage all log4j/slf4j dependencies

Signed-off-by: Chris Hapgood <cch1@hapgoods.com>
Inject log4c dependency conditional on it not already being a dependency