UI Improvements

Major noticeable changes:

* Removed dependency graph button from job list per feedback from Airbnb
* Defaulted epsilon to 30 minutes per feedback from Airbnb
* Normalized lots of font sizes and weights to simplify styles
* Rendered templates that required no interpolation as plain HTML, meaning the user sees something on the page faster than previously
* Rendered initial job list with a single write to the DOM rather than one per list item. This drastically reduced DOM access with long lists and decreased rendering time.

Major implementation changes:

* Removed all requests to Google's font API in favor of a static stylesheet pointing to the public assets. This also removed a `requirejs-plugin` dependency, fewer JS files.
* Upgraded Rivets from 0.4.5 to 0.4.9 and used the JS version instead of the CoffeeScript one to save unnecessary compilation
* Reduced re-rendering that Rivets was handling
* Delegated events in job list instead of adding listeners to each list item. This reduces the number of listeners required by dozens or hundreds with large lists.
* Delegated tooltips in job list instead of adding listeners to each list item. This reduced tooltip listeners from 1-per-item to 1 for the whole list.

Minor bug fixes:

* Deselecting the last job item previously forced a re-render of the entire list, which took a long time with a large list. That no longer happens.
* Sorting the table would not render the correct arrow, depending on where the click occurred. The arrow now always represents the current sort order.

Minor features:

* Theme selector in the bottom left. Try it out.