Added a few more useful repl utilities.

* (>spy some-value) - Kurt was writing this function every 5 mintues, so
  I put it into the repl. All it does is pprint the function parameter
  and return the same parameter.
* Added (use 'print.foo). print-foo contains several utilities to print
  information about executing clojure code. See
  https://github.com/AlexBaranosky/print-foo for more information.