mod for Baidu/checksum gen/some json check/extract. works with pygpsclient

[knormoyle]

I've not done a pull/merge request in a while, so forget how to do it.

Here's what I modified your code to, so it works with pygpsclient on ubuntu. I don't think I broke anything for windows/mac but maybe you could look try.
I translate the Baidu and generate valid checksum. There is one test case in there where I copied data/expected checksum from jetpack output and I match that...and it looks like pygpsclient isn't complaining about the checksums that are translated

some json checking also

I couldn't figure out where to get your email. or I'd email directly.
thanks
-kevin AD6Z

attached file NMEA2TCP_mod.py.gz (gzip'ed)

NMEA2TCP_mod.py.gz