File "rules" has instructional text as comments near top.
2) Convert all text files in repo to LF line ending form.
Any checkout done with "rules" in play will convert the working
tree to native line ending, while keeping repo as LF line ending.
* A track is seen connected to a pad if the track end is inside the pad shape.
* Pads inside pads are now seen connected, if the center of the pad is *inside* the other pad.
* this is made to be sure a large copper area is shared by the 2 pads, and to keep algorithm fast.