Added repair bonus for multiple players

This fixes up a few remaining points from #5666:

* Fixes the player palette not cycling.
* Fixes the 20,20,25,15,20 steps -> 20,20,20,20,20.
* Fixes a couple of remaining minor style nits.
* Split the ISqrt changes out into its own PR (#5767).
`public readonly int[] RepairBonuses = { 100, 150, 175, 200, 220, 240, 260, 280, 300 };` should work