Define and Display a Site Header or Footer for Gerrit Code Review

Gerrit Code Review provides the option of displaying a header/footer in its web UI:

Create an image file or files that you want displayed for the header and/or footer. Place the file or files in
```
<gc_home>/site/etc
```
Create an XML-compliant file named GerritSiteHeader.html in <gc_home>/site/etc. Include a pointer to the image file or files in <gc_home>/site/static that you want to use for the header. Note that this file must be valid XHTML. It is not sufficient for it to be valid HTML. For example, the following example would not work if you left out the superfluous </img> closing tags. This example creates a site header from two image files displayed horizontally as a table row, with a link to the AccuRev web site from the splash image. Example:
```
<div id="gerrit_header">
<table border="0" cellpadding="0" cellspacing="0" id="masthead" width="100%">
<tbody><tr><td valign="center">
<a href="http://www.accurev.com/">
<img height="150" src="static/splash.jpg"></img></a>
</td>
<td width="100%"></td>
<td align="right" valign="bottom">
<img height="150" src="static/titletop.png"></img>
</td>
</tr>
</tbody>
</table>
</div>
```
If you also want a site footer, repeat the previous step for a file named GerritSiteFooter.html.
To enable the display of the header and footer, in the Web UI click Settings > Preferences > Show Site Header.