Added the yweather.py script that provides us the KSpread YWEATHER scripting function.

Those function does use the YAHOO! Weather web service to provide a scripting function that displays the current temperature of a defined location.

So, once those script got executed we are able to;
=YWEATHER("GMXX0151";"c")
where the "GMXX0151" is a US zip code or a Location ID.

You are also able to reference a cell where those location is defined;
=YWEATHER("=C13";"c")