set viewport to help mobile rendering in some html guides

It isn't perfect, but it's mostly there, and is a lot more readable
than the desktop compatibility render.

htmlcssguide.html

@@ -6,6 +6,7 @@
 <link rel="stylesheet" href="javaguide.css">
 <script src="include/styleguide.js"></script>
 <link rel="shortcut icon" href="/styleguide/favicon.ico">
+<meta name="viewport" content="width=device-width, initial-scale=1.0">
 <script src="include/jsguide.js"></script>
 </head>
 <body onload="initStyleGuide();">

javaguide.html

@@ -6,6 +6,7 @@
 <link rel="stylesheet" href="javaguide.css">
 <script src="include/styleguide.js"></script>
 <link rel="shortcut icon" href="/styleguide/favicon.ico">
+<meta name="viewport" content="width=device-width, initial-scale=1.0">
 <script src="https://cdn.jsdelivr.net/gh/google/code-prettify@master/loader/run_prettify.js"></script>
 </head>
 <body onload="initStyleGuide();">

jsguide.html

@@ -6,6 +6,7 @@
 <link rel="stylesheet" href="javaguide.css">
 <script src="include/styleguide.js"></script>
 <link rel="shortcut icon" href="/styleguide/favicon.ico">
+<meta name="viewport" content="width=device-width, initial-scale=1.0">
 <script src="include/jsguide.js"></script>
 </head>
 <body onload="initStyleGuide();">

tsguide.html

@@ -6,6 +6,7 @@
 <link rel="stylesheet" href="javaguide.css">
 <script src="include/styleguide.js"></script>
 <link rel="shortcut icon" href="/styleguide/favicon.ico">
+<meta name="viewport" content="width=device-width, initial-scale=1.0">
 <script src="include/jsguide.js"></script>
 </head>
 <body onload="initStyleGuide();">