Track additional events

The goal is to eventually add tracking for the following actions:

* Click the "help" button at the top of the page
* Hover over the "more info" icons

This is an early review so that I can get early directional feedback before investing too heavily in a particular approach.
The convention we've been following is to declare all the vars together--something like:
```
var $el = $(content),
    properties = ...
```

The [airbnb style guide](https://github.com/airbnb/javascript#variables) has some examples if you're curious and with great variables names!