Remove unneeded conditional require

I got slightly carried away with the big commit and didn't think
that you'll never have tools.nrepl loaded if you're using
cider-nrepl.main.

Additionally - we'll likely kill this ns completely down the road,
and leverage functionality now in nREPL directly.

Author: bbatsov

src/cider_nrepl/main.clj

@@ -1,12 +1,7 @@
 (ns cider-nrepl.main
   (:require
-   [clojure.java.io :as io]))
-
-(if (find-ns 'clojure.tools.nrepl)
-  (require
-   '[clojure.tools.nrepl.server :as nrepl.server])
-  (require
-   '[nrepl.server]))
+   [clojure.java.io :as io]
+   nrepl.server))
 
 (defn- require-and-resolve
   [thing]