optimize revlog.lookup when passed hex(node)[:...]
Instead of converting each node from the filenode to a hex form,
convert the arg to a bin form.
For a revlog with 26711 entries, doing 100 lookup:
before: ~18s
after : ~13s
<table class="slogEntry parity#parity#">
<tr>
<td class="age">#date|age#</td>
<td class="author">#author|obfuscate#</td>
<td class="node"><a href="?cs=#node|short#">#desc|strip|firstline|escape#</a></td>
</tr>
</table>