Precision Frequency Measurement of 87Rb 5S1/2 (F = 2)→5D5/2 (F″ = 4) Two-Photon Transition through a Fiber-Based Optical Frequency Comb*Supported by the National Natural Science Foundation of China under Grant Nos 61405002, 91336103, 10934010, 61535001 and 61078026. (May 2016)