[aprssig] Weather warning page

[Steve Dimse]

I added a new cgi to findU, warn-page.

Previously warn-near.cgi and the new warn rss feed pointed to warn- 
text.cgi to display individual warnings as a simple text page. The  
new page has a table layout similar to other findU pages, and  
automatically includes the radar image for the area with the warning.  
Example:

http://www.findu.com/cgi-bin/warn-page.cgi?id=OUNS1356z

The old warn-text.cgi is still available, I know some people were  
doing parsing of this, so I created a new cgi instead of changing the  
existing one, nothing should be broken...

Steve K4HG