Attempt at updated FreeBSD rc script

[Rob Sullivan]

Hi Tom, Gary, Matthew and all contributors,

Thank you for the awesomeness that is weewx, been a user since ~2013 (first on QNAP, now in a FreeBSD 12.2 jail inside TrueNAS Core 12).  If you ever want to see what the weather is doing in Yarrawarrah, southern Sydney, NSW, Australia: Yarrawarrah Weather Station.

I finally got around to getting my rc script sorted on FreeBSD and noticed the weewx.bsd rc script in /weather/weewx/util/init.d did work on jail startup. 

After a bit of hacking I came up with the attached - is it of value?  Someone more fluent would be able to tune or make more elegant...

Thanks again!

Rob