Generally revise county speed limits

This bill amends Montana law to clarify how local authorities and county commissioners can set speed limits on roads within their jurisdiction. It allows local officials to adjust speed limits based on engineering and traffic studies, with specific rules for urban areas, rural roads, school zones, and senior citizen centers. County commissioners can set limits on county roads without requiring a formal engineering study, while local authorities must consult with school officials when establishing school zones. The bill also clarifies that variable speed limits are permitted if they comply with existing state regulations and that violations of these limits remain misdemeanor offenses.