Update readme.txt details, trying to wrangle pre/code tag display with markdown, et al

git-svn-id: https://plugins.svn.wordpress.org/prismatic/trunk@1974533 b8457f37-d9ea-0310-8a92-e5e31aec5664

readme.txt

@@ -320,7 +320,7 @@ So for example, to specify a code block as C++, you would write:
 	
 	Alternate: <pre class="language-cpp"><code class="optional">...</code></pre>
 
-Note: in the previous example, ignore the `class="optional"` added to the `<code>` tag (for the "Alternate" syntax); it is used to prevent markdown from mangling the code example.
+Note: in the previous example, ignore the `class="optional"` added to the code tag (for the "Alternate" syntax); it is used to prevent markdown from mangling the code example.
 
 To disable Prism.js syntax highlighting for any snippet, simply omit the language class. 
 
@@ -390,7 +390,7 @@ So for example, to specify a code block as C++, you would write:
 	
 	Alternate: <pre class="language-cpp"><code class="optional">...</code></pre>
 
-Note: in the previous example, ignore the `class="optional"` added to the `<code>` tag (for the "Alternate" syntax); it is used to prevent markdown from mangling the code example.
+Note: in the previous example, ignore the `class="optional"` added to the code tag (for the "Alternate" syntax); it is used to prevent markdown from mangling the code example.
 
 To disable Highlight.js syntax highlighting for any code block, add a class of `nohighlight`, like so: