This is for #134 – adds copy/paste buttons to the second row of tools, and keeps them in a disabled state for now, while they’re not usable. It also moves icons into a subfolder, given their proliferation in the paint editor component
This adds formatting and icons to the edit field buttons at the top of the ui, as well as some additional components for abstraction – such as `InputGroup`, `ButtonGroup` and `EditFieldButton` (which is a subcomponent of the paint editor)
