Sounds like the OP was riding in full compliance with state law (no state requires cyclists to have mirrors nor to use lights during the daytime, nor are cyclists required to ride in a parking lane). Since this is his commute route he may well encounter the same officer again in the future. So I'd suggest he write to the head of the local police department indicating that he felt this was an unjustified stop, outlining relevant state law in support, and requesting that officers be instructed not to stop or otherwise inconvenience lawful cyclists.