Before: We drew 2 fontawesome comment icons, on on top of the other
After: Moved icon into iD spritesheet and gave it an actual `stroke` property that can be styled
- I made the buttons work like GitHub comment-on-issue buttons
before typing: "Close Note" / "Comment" (disabled)
after typing: "Close and Comment" / "Comment" (enabled)
- I removed a bunch of the event dispatches. These are useful for sending
events to listeners/observers outside of the module. In this case I think
we can handle most of the things from within the uiNoteEditor. We can still
dispatch an 'update' event so that modeSelectNote can reselect and redraw
the note after some change happens to it.
TODO - make the buttons work / check the OSM API stuff.
This sets `pointer-events: none` for the `.note-shadow` class,
to fix an amusing bug where hovering over the filled part of the comment
icon would work ok but hovering over the "dots" would not.
