GUI -- Topo View - change default map to be continental US.

Change-Id: Iba696a6c61f72732dcbdf7b80c7f263e176a6182
diff --git a/web/gui/src/main/webapp/app/view/topo/topo.js b/web/gui/src/main/webapp/app/view/topo/topo.js
index 29fcc83..1ec18b9 100644
--- a/web/gui/src/main/webapp/app/view/topo/topo.js
+++ b/web/gui/src/main/webapp/app/view/topo/topo.js
@@ -312,7 +312,7 @@
     function setUpMap($loc) {
         var s1 = $loc.search().mapid,
             s2 = ps.getPrefs('topo_mapid'),
-            mapId = s1 || (s2 && s2.id) || 'world',
+            mapId = s1 || (s2 && s2.id) || 'usa',
             promise,
             cfilter,
             opts;