release: 0.6.0: Delivery detail page, DNS badge, machine metrics, wide layout

A page per delivery (`/deliveries/{id}`), reached from the *Details* link on
Added:
  - A page per delivery (`/deliveries/{id}`), reached from the *Details* link on
  - A **DNS** badge in the domain list, one per row, carrying the same
  - Machine metrics on the status page: a **Machine** card reporting the
  - An index of the current page's own sections in the navigation column, for the
Changed:
  - Every panel page is laid out in one column of the same width, so moving
  - The mark's small-size variant — the tab icon and the `SP` initials it
  - The stamp's `SELF-HOSTED SMTP RELAY` line is set at 11.5/0.15 instead of
  - The delivery log lists what identifies a message and nothing else: time,
  - Subjects are decoded for display as well as on the way in, so the rows the
  … (4 more in CHANGELOG)

Full detail: CHANGELOG.md (0.6.0).

internal/web/templates/status.html

@@ -5,7 +5,7 @@
 
 {{template "status_body" .}}
 
-<div class="card">
+<div class="card" id="hostname">
   <h2>Hostname and reverse DNS <span class="st st-{{.PTR.Status}}">{{.PTR.Status}}</span></h2>
   <p class="muted">Receiving servers check that the name this server announces
   resolves to its address <em>and</em> that the address resolves back to the same
@@ -29,7 +29,7 @@
   </form>
 </div>
 
-<div class="card">
+<div class="card" id="configuration">
   <h2>Configuration</h2>
   <p class="muted">Regenerates the OpenDKIM and Postfix configuration from the
   database and reloads both daemons. Use it if you edited the files by hand,
@@ -41,3 +41,22 @@
   </form>
 </div>
 {{end}}
+
+{{/* The status page's section index, shown in the navigation column (see the
+     "sections" block in layout.html). The first six cards are the ones the
+     polling fragment replaces every five seconds; their ids are part of
+     status_body.html and do not change with the reading, so the links here hold
+     across a refresh. */}}
+{{define "sections"}}
+<div class="sections">
+  <p class="sections-title">On this page</p>
+  <a href="#overall">Overall</a>
+  <a href="#processes">Processes</a>
+  <a href="#machine">Machine</a>
+  <a href="#queue">Mail queue</a>
+  <a href="#certificate">TLS certificate</a>
+  <a href="#sockets">Milter sockets</a>
+  <a href="#hostname">Hostname and reverse DNS</a>
+  <a href="#configuration">Configuration</a>
+</div>
+{{end}}