Better-expose Wyoming upper air

[dopplershift]

• Add to API docs
• Add examples
• Maybe import into simplewebservice?

[illston]

I am occasionally getting the following error.

"HTTPError: Error accessing http://weather.uwyo.edu/cgi-bin/sounding/?region=naconf&TYPE=TEXT%3ALIST&YEAR=1999&MONTH=05&FROM=0400&TO=0400&STNM=OUN: 503 Sorry, the server is too busy to process your request.
Please try again later."

From the following code:

from siphon.simplewebservice.wyoming import WyomingUpperAir
dataset = WyomingUpperAir.request_data(datetime(1999, 5, 4, 0), 'OUN')

Rerunning the script will eventually correct the situation. I saw there was a request for them to give a 503 error code at:
Unidata/MetPy#435

[jrleeman]

Right - they are getting swamped by someone and going down.