Basic test plumbing

Initial stab for running ```grunt test```.

I followed the link added in CONTRIBUTING which was good enough to write 2 tiny tests.
1. tests/index.html which is just a sanity test for now.
1. tests/storage.html which only tests for the local bin

I'm not sure whether the 4 commits are OK for you? See my blog [Do we need git squash and thus forced pushes?](http://build2be.com/content/do-we-need-git-squash-and-thus-forced-pushes)

I have some more tests in my dreditor sandbox to be added after this is accepted.

- [ ] Can we exclude the ```tests/lib``` directory? And add it to .gitignore?