Fix Issue #277. Make test page work in Chrome

Fixing Issue #277. Too many people use Chrome to leave the test/learn page broken. Put copies of the test files directly into the dust_files folder for now. We can either updated them when we add new tests or, more likely only update them when there are significant new features to demonstrate like a new helper. For the most part, I think people look at some of these but often just prototype their dust work in the test tool so current versions of all tests is not a big deal.  One day we can pursue submodules.