This is now in compliance with the spec, using a single color with
opacity to render open/hovered/active GridItems and InfoPanels. We also
properly show background on open GridItems.
This patch extracts InfoPanel from IconGridItem, adds style tweaks to
match the spec, and in general reduces prop-drilling by tapping into
recoil state for most config, and making use of IconContext to style
member icons where appropriate :)
