Remove unused patch file.

It looks like this was included accidentally.

Thanks to mark4o for pointing out I'd missed this in the previous
removal.

doc/header.html.patch

---- header.orig.html	2012-06-11 00:32:03.320461381 -0400
-+++ header.html	2012-06-11 01:08:42.943446484 -0400
-@@ -18,16 +18,21 @@
- <div id="titlearea">
- <table cellspacing="0" cellpadding="0">
-  <tbody>
-- <tr style="height: 56px;">
-+ <tr style="height: 64px;">
-   <!--BEGIN PROJECT_LOGO-->
-   <td id="projectlogo"><img alt="Logo" src="$relpath$$projectlogo"/></td>
-   <!--END PROJECT_LOGO-->
-   <!--BEGIN PROJECT_NAME-->
-   <td style="padding-left: 0.5em;">
--   <div id="projectname">$projectname
--   <!--BEGIN PROJECT_NUMBER-->&#160;<span id="projectnumber">$projectnumber</span><!--END PROJECT_NUMBER-->
--   </div>
-+  <div id="projectname"><img src="opus_logo.svg" width=112 height=64 alt="Opus"/><!--$projectname--></div>
-+  </td>
-+  <td><table style="padding-left: 0.5em;" cellspacing="0" cellpadding="0"><tbody>
-+   <tr><td>
-    <!--BEGIN PROJECT_BRIEF--><div id="projectbrief">$projectbrief</div><!--END PROJECT_BRIEF-->
-+   </td></tr>
-+  <td><!--BEGIN PROJECT_NUMBER--><span id="projectnumber">$projectnumber</span><!--END PROJECT_NUMBER-->
-+   </td></tr>
-+   </table>
-   </td>
-   <!--END PROJECT_NAME-->
-   <!--BEGIN !PROJECT_NAME-->