To fix ClassCastException

[ Issue Description ]
1. Install clojuresque plugin correctly.
2. Run clojureRepl task directly.
Expected Result:
1. A new NREPL instance should run on port 7888.
Actual Result:
1. Throw ClassCastException at line 11 in clojuresque/tasks/repl.clj.

[ Solution ]
1. Modify ClojureRepl.groovy and transform port to String before calling API.
2. Modify repl.clj.
I choose the former.