docs: consolidate html header and footer

add doctype
add character encoding
add missing <head> tag
unify html header and footer

Signed-off-by: Brian Paul <brianp@vmware.com>
diff --git a/docs/shading.html b/docs/shading.html
index aba3959..604bd1d 100644
--- a/docs/shading.html
+++ b/docs/shading.html
@@ -1,12 +1,13 @@
-<HTML>
+<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
+<html lang="en">
+<head>
+  <meta http-equiv="content-type" content="text/html; charset=utf-8">
+  <title>Shading Language Support</title>
+  <link rel="stylesheet" type="text/css" href="mesa.css">
+</head>
+<body>
 
-<TITLE>Shading Language Support</TITLE>
-
-<link rel="stylesheet" type="text/css" href="mesa.css"></head>
-
-<BODY>
-
-<H1>Shading Language Support</H1>
+<h1>Shading Language Support</h1>
 
 <p>
 This page describes the features and status of Mesa's support for the
@@ -264,5 +265,5 @@
 The Mesa demos repository also has some good GLSL tests.
 </p>
 
-</BODY>
-</HTML>
+</body>
+</html>