docs: Add {mpd,http}/zeroconf descriptions

docs/changelog.rst

@@ -30,13 +30,17 @@ v0.17.0 (UNRELEASED)
 
 - The MPD service is now published as a Zeroconf service if avahi-deamon is
   running on the system. Some MPD clients will use this to present Mopidy as an
-  available server on the local network without needing any configuration.
+  available server on the local network without needing any configuration. See
+  the :confval:`mpd/zeroconf` config value to change the service name or
+  disable the service. (Fixes: :issue:`39`)
 
 **HTTP frontend**
 
 - The HTTP service is now published as a Zeroconf service if avahi-deamon is
   running on the system. Some browsers will present HTTP Zeroconf services on
-  the local network as "local sites" bookmarks.
+  the local network as "local sites" bookmarks. See the
+  :confval:`http/zeroconf` config value to change the service name or disable
+  the service. (Fixes: :issue:`39`)
 
 
 v0.16.1 (2013-11-02)

docs/ext/http.rst

@@ -59,6 +59,13 @@ Configuration values
     Change this to have Mopidy serve e.g. files for your JavaScript client.
     "/mopidy" will continue to work as usual even if you change this setting.
 
+.. confval:: http/zeroconf
+
+    Name of the HTTP service when published through Zeroconf. The variables
+    ``$hostname`` and ``$port`` can be used in the name.
+
+    Set to an empty string to disable Zeroconf for HTTP.
+
 
 Usage
 =====

docs/ext/mpd.rst

@@ -97,6 +97,13 @@ Configuration values
     Number of seconds an MPD client can stay inactive before the connection is
     closed by the server.
 
+.. confval:: mpd/zeroconf
+
+    Name of the MPD service when published through Zeroconf. The variables
+    ``$hostname`` and ``$port`` can be used in the name.
+
+    Set to an empty string to disable Zeroconf for MPD.
+
 
 Usage
 =====