Run this to save your HTTPS credentials:
git config credential.helper store
You need to clone recursively:
git clone --recursive https://github.uiowa.edu/hbwhite/blocka.git
To test the code (you'll want to run a server locally otherwise JavaScript will have access to your files via the file:// protocol which is unsecured):
cd blocka/ && python -m SimpleHTTPServer 8080
...and then browse it at http://localhost:8080