Fix JS error when computing tab wrapping.

[bedney]

When computing tab wrapping behavior, these check expressions will error at the boundary (when i is 0 or is at the last index). This patch checks i at these boundaries before it performs the other check.

[matthewp]

Awesome! Can you include a test?

[bedney]

So that's fine, but I'm having trouble running the unit tests. I tried 'npm test' and phantomjs was hanging, so I switched testee's target browser to chrome and I noticed that I'm getting errors in the index.html page about not being able to find QUnit resources. Any suggestions?

[matthewp]

did you run npm install and bower install? Try testing from a local browser first.

[bedney]

Ok, got the tests running and updated the forward tabbing test to show wrap behavior. The reverse tabbing test was already showing wraparound... which is interesting since it must've been passing. In any case, feel free to look at this and let me know. This is my first time committing to this codebase.