Abstract ancestor algorithm into generic function
Make depth calculation non-recursive
Add simple shortcut for linear ancestry
Convert context to use ancestor function
make memoized parents function
Convert revlog to use ancestor function
<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>