Add classification for tablet-microsoft.

As requested in issue #19.

controlset.txt

@@ -27,3 +27,7 @@ mobile-iphone	AppleCoreMedia/1.0.0.9B206 (iPhone; U; CPU OS 5_1_1 like Mac OS X;
 tablet-ipad	Mozilla/5.0 (iPad; U; CPU iPhone OS 5_1_1 like Mac OS X; en_US) AppleWebKit (KHTML, like Gecko) Mobile [FBAN/FBForIPhone;FBAV/4.1.1;FBBV/4110.0;FBDV/iPad2,1;FBMD/iPad;FBSN/iPhone OS;FBSV/5.1.1;FBSS/1; FBCR/;FBID/tablet;FBLC/en_US;FBSF/1.0]
 
 mobile-smartphone	Mozilla/5.0 (BB10; Touch) AppleWebKit/537.10+ (KHTML, like Gecko) Version/10.0.9.2372 Mobile Safari/537.10+
+
+#
+pc	Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; .NET4.0C; .NET4.0E; Tablet PC 2.0)
+tablet-microsoft	Mozilla/5.0 (Windows NT 6.3; ARM; Trident/7.0; Touch; .NET4.0E; .NET4.0C; Tablet PC 2.0; rv:11.0) like Gecko

devicedetect.vcl

@@ -61,6 +61,7 @@ sub devicedetect {
 		elsif (req.http.User-Agent ~ "PlayBook; U; RIM Tablet")         { set req.http.X-UA-Device = "tablet-rim"; }
 		elsif (req.http.User-Agent ~ "hp-tablet.*TouchPad")         { set req.http.X-UA-Device = "tablet-hp"; }
 		elsif (req.http.User-Agent ~ "Kindle/3")         { set req.http.X-UA-Device = "tablet-kindle"; }
+		elsif (req.http.User-Agent ~ "Touch.+Tablet PC")            { set req.http.X-UA-Device = "tablet-microsoft"; }
 		elsif (req.http.User-Agent ~ "Mobile.+Firefox")     { set req.http.X-UA-Device = "mobile-firefoxos"; }
 		elsif (req.http.User-Agent ~ "^HTC" ||
 		    req.http.User-Agent ~ "Fennec" ||