MADISON, Wis. — The Wisconsin Supreme Court today upheld the 2011 law that effectively ended collective bargaining for most public workers, sparked massive protests and led to Republican Gov. Scott Walker’s recall election and rise to national prominence. The 5-2 ruling upholds the Walker’s signature policy achievement in its entirety and is a major victory for the potential 2016 GOP presidential candidate, who is seeking re-election this year. The ruling also marks the end of the three-year legal …