added sample application for debugging

added a debug folder to the repository with a sample.html file to assist new developers in referencing local, unminified source files.

more sophisticated logic for injecting scripts could be substituted later if desired.
I would suggest replacing this line w/ some comments instructing devs to place the code they want to test in an external script in this folder (like debug.js) which we would add to .gitignore. That way devs could include their own debugging logic w/o accidentally checking in their changes to this file.