documented support for <meta>

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@5477 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

docs/latex/wx/htmltags.tex

@@ -181,6 +181,9 @@ AREA            SHAPE=POLY
                 COORDS=[coords]
                 HREF=[url]
                 
+META            HTTP-EQUIV="Content-Type"
+                CONTENT=[string]
+                
 \end{verbatim}