For “Mr. Gainesville,” as Bob Hamrick is affectionately called by colleagues, the decision to step away from city government after 46 years in office was not easy and certainly unexpected. After all, it was thought that Hamrick, 87, might very well be the longest-serving elected official at any level of politics in the entire nation when he announced this summer that he would retire from City Council at the end of the year. Hamrick came on at a time when the police station was located beneath City Hall, when a Woolworths dominated the downtown landscape and when raw sewage was frequently seen flowing through the area’s slums.