Reduce CPU consumption if UI cannot connect to backend

* blank keyframes for blinking Connect animation
* increased topology API retry timer interval

Fixes #1220

client/app/scripts/utils/web-api-utils.js

@@ -112,7 +112,7 @@ export function getTopologies(options) {
       receiveError(url);
       topologyTimer = setTimeout(() => {
         getTopologies(options);
-      }, TOPOLOGY_INTERVAL / 2);
+      }, TOPOLOGY_INTERVAL);
     }
   });
 }

client/app/styles/main.less

@@ -994,7 +994,7 @@ h2 {
   }
 
   &.status-loading {
-    animation: blinking 2.0s infinite @base-ease;
+    animation: blinking 2.0s 150 @base-ease; // keep blinking for 5 minutes
     text-transform: none;
     color: @text-color;
   }
@@ -1007,7 +1007,7 @@ h2 {
   &:last-child {
     margin-bottom: 0;
   }
-  
+
   .fa {
     margin-left: 4px;
     color: darkred;
@@ -1059,9 +1059,9 @@ h2 {
 }
 
 @keyframes blinking {
-  0%, 100% {
+  0%, 50%, 100% {
     opacity: 1.0;
-  } 50% {
+  } 25% {
     opacity: 0.5;
   }
 }