add refresh button to mqtt peers dialog

xwords4/android/app/src/main/java/org/eehouse/android/xw4/BoardDelegate.java

@@ -427,6 +427,12 @@ public class BoardDelegate extends DelegateBase
                 .setTitle( R.string.menu_about_peers )
                 .setView( psv )
                 .setPositiveButton( android.R.string.ok, null )
+                .setNegativeButton( R.string.button_refresh, new OnClickListener() {
+                        @Override
+                        public void onClick( DialogInterface dlg, int bttn ) {
+                            showDialogFragment( DlgID.MQTT_PEERS );
+                        }
+                    } )
                 .create();
         }
             break;

xwords4/android/app/src/main/res/values/tmpstrings.xml

@@ -7,5 +7,6 @@
 
   <string name="peers_info_pending">Querying server…</string>
   <string name="no_peers_info">Peers information not available</string>
+  <string name="button_refresh">Refresh</string>
 
 </resources>