Fixed units not moving to the rallypoint

I played around and made some observations.

* `public int nearEnough = 1;` is the only value that makes sense as 0 crashes the game and 2 will be too far away for the default exit and rally point distance. Also the value is looked up somewhere else and not even configurable so why was this even a public field.
* MoveWithinRange seems to be a bad choice for rally point movement as units are allowed to give up too early. We want them to move directly to that point not stand somewhere near it blocking the exit. This fixes #5682.

The StyleCop violations and legacy int[] fields to parse a 2D vector coordinate make this look like code that has not been touched for years. Hope this removes some bit rot.