notify: add option for deterministic message-id generation
Copied from email by durin42:
> Pierre-Yves asked offline why I asked a new option for this and why it
> is not the default. Message-Id is supposed to be unique world-wide and
> while it is desirable to have a deterministic mechanism for them for
> creating follow-up emails, it needs organisational control for ensuring
> the uniqueness.
Differential Revision: https://phab.mercurial-scm.org/D6824
<entry>
<title>{inbranch%"{if(name, '[{name|escape}] ')}"}{branches%"{if(name, '[{name|escape}] ')}"}{desc|strip|firstline|strip|escape|nonempty}</title>
<id>{urlbase}{url|urlescape}#changeset-{node}</id>
<link href="{urlbase}{url|urlescape}rev/{node|short}"/>
<author>
<name>{author|person|escape}</name>
<email>{author|email|obfuscate}</email>
</author>
<updated>{date|rfc3339date}</updated>
<published>{date|rfc3339date}</published>
<content type="xhtml">
<table xmlns="http://www.w3.org/1999/xhtml">
<tr>
<th style="text-align:left;">changeset</th>
<td>{node|short}</td>
</tr>
<tr>
<th style="text-align:left;">branch</th>
<td>{inbranch%"{name|escape}"}{branches%"{name|escape}"}</td>
</tr>
<tr>
<th style="text-align:left;">bookmark</th>
<td>{bookmarks%"{name|escape}"}</td>
</tr>
<tr>
<th style="text-align:left;">tag</th>
<td>{tags%"{name|escape}"}</td>
</tr>
<tr>
<th style="text-align:left;">user</th>
<td>{author|obfuscate}</td>
</tr>
<tr>
<th style="text-align:left;vertical-align:top;">description</th>
<td>{desc|strip|escape|websub|addbreaks|nonempty}</td>
</tr>
<tr>
<th style="text-align:left;vertical-align:top;">files</th>
<td>{files}</td>
</tr>
</table>
</content>
</entry>