Support Old BoxCar CSV Files

[riggsd]

The old BoxCar Pro software produced a more limited CSV output than does HOBOWare. Consider adding seamless support for these files (which were likely produced in the old "hockey puck" H08 days).

I don't have access to BoxCar Pro anymore, but it looks like this may be an example of its default output with a HOBO H08:

Date Time	Temperature (*C) c:1	High-Res Temp (*C) c:1 2	RH (%) c:3
07/07/03 10:45:40.0	26.34	26.22	48.3
07/07/03 11:45:40.0	24.4	24.35	44.2
07/07/03 12:45:40.0	22.86	22.76	45.7
07/07/03 13:45:40.0	22.86	22.69	46.7

[riggsd]

According to the specifications, Temperature uses 8-bit resolution, High-Res Temp uses 12-bit resolution, and the H08 could be configured to record either or both(!) simultaneously. We should prefer the 12-bit temperature value if both are available, and fall back to 8-bit otherwise.

It also says "The relative humidity sensor range is 0 to 100% RH. It can read up to 104.1% in a condensing environment. While the sensor is saturated, you will not get accurate readings." How should we treat RH values greater than 100%?