hgweb: rename 'changesetbaseline' template to 'difffrom'
More accurately reflects what it will be used for, and is also shorter.
This template is used to change which rev the current rev is diff'd
against. For example, if you're at '/rev/P1:REV', this would link to a
path like '/rev/P2:REV'.
Example usage in a template:
{parent%difffrom}
{header}
<title>{repo|escape}: error</title>
</head>
<body>
<div class="container">
<div class="menu">
<div class="logo">
<a href="{logourl}">
<img src="{staticurl}{logoimg}" width=75 height=90 border=0 alt="mercurial" /></a>
</div>
<ul>
<li><a href="{url}shortlog{sessionvars%urlparameter}">log</a></li>
<li><a href="{url}graph{sessionvars%urlparameter}">graph</a></li>
<li><a href="{url}tags{sessionvars%urlparameter}">tags</a></li>
<li><a href="{url}bookmarks{sessionvars%urlparameter}">bookmarks</a></li>
<li><a href="{url}branches{sessionvars%urlparameter}">branches</a></li>
</ul>
<ul>
<li><a href="{url}help{sessionvars%urlparameter}">help</a></li>
</ul>
</div>
<div class="main">
<h2 class="breadcrumb"><a href="/">Mercurial</a> {pathdef%breadcrumb}</h2>
<h3>error</h3>
<form class="search" action="{url}log">
{sessionvars%hiddenformentry}
<p><input name="rev" id="search1" type="text" size="30"></p>
<div id="hint">find changesets by author, revision,
files, or words in the commit message</div>
</form>
<div class="description">
<p>
An error occurred while processing your request:
</p>
<p>
{error|escape}
</p>
</div>
</div>
</div>
{footer}