If you don’t smoke and you find yourself walking behind someone who does, it can be unpleasant. Now a New York City Councilman wants to do something about it. “My bill is very simple: no smoking and walking on New York City sidewalks,” said Queens Councilman Peter Koo (Dist. 20). His bill would make it a misdemeanor to walk while smoking, likely punishable by a fine of $50. Smokers, already banned from lighting up in public parks among many other places in the city, weren’t thrilled at the idea. …