help: move "revision syntax" help topics into online help
Move the "Specifying Single Revisions" and "Specifying Multiple
Revisions" help topics from the manual page into the helptable
so they are available both online and in the manual page.
<table class="slogEntry parity#parity#">
<tr>
<td class="age">#date|age#</td>
<td class="author">#author|person#</td>
<td class="node"><a href="#url#rev/#node|short#{sessionvars%urlparameter}">#desc|strip|firstline|escape#</a></td>
</tr>
</table>