added visual cues to inspecting content and fixed the activity calendar

I found the modal that popped up when inspecting content annoying so I switched it out in favor of a visual cue. All items now turn blue so the user should (hopefully) know they can click on it to view the JSON.

Also fixed #50 which was caused by the [deprecation of the `getYear()` method](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/getYear).