Fix showing build steps in the machine status page

This was broken because of the comparison

  step.machine.match('@(.*)').0 == m.key

where m.key contains the SSH user.

Also some style tweaks.

src/root/status.tt

@@ -14,7 +14,7 @@
         <td><a href="[% c.uri_for('/build' step.build.id) %]">[% step.build.id %]</a></td>
         <td><a class="row-link" href="[% c.uri_for('/build' step.build.id 'nixlog' step.stepnr 'tail-reload') %]">[% step.stepnr %]</a></td>
         <td><tt>[% step.drvpath.match('-(.*)').0 %]</tt></td>
-        <td class='right'>[% INCLUDE renderDuration duration = curTime - step.starttime %] </td>
+        <td style="width: 10em">[% INCLUDE renderDuration duration = curTime - step.starttime %] </td>
       </tr>
     [% END %]
   </tbody>