ui for adding tags (#16).
better class names and icons (#16).
Tag model + specs (#16).
integrated tags with mutations. works with views and controllers as well (#16).
trying to get tags to sort (#16).
trying to get it to filter (#16).
can now hide notes when you click on a note — it just cannot un-hide them (#16).
filtering by tag now works. could use refactor and easing, but functional (#16).
merge from 16-tags.