refactored for running coffeescript tests, and added #458 test in coffee...

issue #458 was closed as it could not be recreated. 

However, the proving test was created in JS  - the bug exists only for coffeescript.

I have added coffscript test support, and converted the test for coffeescript. The test currently fails.

I updated the "test" script in package.json to run coffeescript tests also.
I have never done `coffeescript` but dont you have ti install it before you can run the `coffee` command.
I dint see any update into `package.json` file.