Replace kdtree with geokdtree
Adjusted Spec to use geokdtree class names
Removing debugging statement.
Swapping the 'debugger' gem for 'ruby-debug' which is jRuby compatible.
Merge pull request #1 from digitalreasoning/jruby_compat

This PR swaps CRuby gems for JRuby compatible gems (kdtree => geokdtree, debugger => ruby-debug).