Everytown for Gun Safety, a national nonprofit advocacy group, has ranked California first in the nation for the strength of its gun control laws. “For over a decade, our grassroots army has worked in lockstep with our gun safety champions to keep California families safe from senseless acts of gun violence — this ranking showcases how far we’ve come and the road ahead,” said Cassandra Whetstone, a volunteer with the California chapter of Moms Demand Action, in a statement Thursday. One of the laws, though, is being challenged in court by gun rights groups. The measure bars carrying concealed …