New Jersey Gov. Chris Christie, who has spent much of the last year trying to weaken the medical marijuana law signed by his predecessor, announced new regulations Friday that made several concessions to patient advocates, but in many respects remain unjustly prohibitive. In either case, the latest proposal may finally allow for the first medical marijuana sales in New Jersey to take place as soon as this summer. Under the new rules: New Jersey will become home to six legal growing sites and…