Commit 3-30-16: Added Icons

Replacement field with green plus button on the right

Icons have been added to the config to make it look better. They may be added elsewhere soon.

At this time, I am enough satisfied with the UI to mark it as complete. All that is left is dealing with the toggleActive bug and (if possible) the image linking bug. Once those are fixed, the extension will be ready to publish. Thank you for reading.