Refactored IconFactory to be more self contained
Updated Handlebars helper to insert icon for offense type

- also a bit more styling for legend
Adding icons that were referenced in the code

Some of these icons were originated from
[here](http://mapicons.nicolasmollet.com/markers/)
Updated README to fix a few typos
Added icon size and ancors for icons.

- Really should rework for a more DRY approach