Move console script from bin/ to script/

Let's consolidate down to a single directory for our scripts.

Author: rmacklin

README.md

@@ -177,7 +177,7 @@ test environment and run `script/test` to run the tests. By default, that will
 exercise the `demo_app` example application. To exercise a different example
 application, set the `EXAMPLE_APP` environment variable to the corresponding
 directory name (e.g. `EXAMPLE_APP=demo_app-rollup`). You can also run
-`bin/console` for an interactive prompt that will allow you to experiment.
+`script/console` for an interactive prompt that will allow you to experiment.
 
 To install this gem onto your local machine, run `bundle exec rake install`. To
 release a new version, update the version number in `version.rb`, and then run