Add class that disables the normalize whitespace plugin

plugins/normalize-whitespace/index.html

@@ -42,6 +42,9 @@ <h1>How to use</h1>
 	<p>By default the plugin trims all leading and trailing whitespace of every code block.
 	It also removes extra indents and trailing whitespace on every line.</p>
 
+	<p>The plugin can be disabled for a particular code block by adding the class <code>no-whitespace-normalization</code> to
+	either the <code>&lt;pre></code> or <code>&lt;code></code> tag.</p>
+
 	<p>The default settings can be overridden with the <code class="language-javascript">setDefaults()</code> method
 	like so:</p>
 

plugins/normalize-whitespace/prism-normalize-whitespace.js

@@ -128,8 +128,10 @@ Prism.plugins.NormalizeWhitespace = new NormalizeWhitespace({
 
 Prism.hooks.add('before-highlight', function (env) {
 	var pre = env.element.parentNode;
+	var clsReg = /\bno-whitespace-normalization\b/;
 	if (!env.code || !pre || pre.nodeName.toLowerCase() !== 'pre' ||
-			(env.settings && env.settings['whitespace-normalization'] === false))
+			(env.settings && env.settings['whitespace-normalization'] === false) ||
+			clsReg.test(pre.className) || clsReg.test(env.element.className))
 		return;
 
 	var children = pre.childNodes,