Belt Speed Hints

[SignpostMarv]

• hint number of belts & what speed is required to handle a given item
• popover to show breakdown of all belt speeds (i.e. if amount can be satisfied by 1x mk.5, show how many mk.1-mk.4 belts are needed)
• support for pipe speeds also
• state/collection/group/pool-level settings for configuring max belt/pipe speed