Fixed Meiligao VT300 protocol when ACC Mileage is disabled.

I have a VT300 tracker that sends data below when "ACC accumulated mileage" is disabled: 

2013-02-25 21:01:35 org.traccar.BasePipelineFactory$StandardLoggingHandler.log FINE: [20109 <- 98.129.164.1] - (HEX: 2424005f5977203744058499553032303131372e3030302c412c343131372e393231322c4e2c30383133302e323039362c572c302e30302c3330332e38352c3236303231337c312e367c30307c303030307c303030302c3030303071cd0d0a)

A fix and test case were added for this.