Change wget agent

http://whatsmyuseragent.com/

using with wget -U 'AGENT' to check whether wget work.

hvn@hvnatvcc: ~/python/NetChecker/bin $ wget http://whatsmyuseragent.com/

hvn@hvnatvcc: ~/python/NetChecker/bin $ wget -U 'Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:13.0) Gecko/20100101 Firefox/13.0.1' http://whatsmyuseragent.com/ 

return other result