Add messaging when archived build logs loads fail.

This code also checks for an ad blocker, and adjusts the message accordingly.

Fixes #184

static/css/directives/ui/build-logs-view.css

@@ -9,6 +9,11 @@
   min-height: 100px;
 }
 
+.build-logs-view .co-alert {
+  margin-bottom: 0px;
+  color: black !important;
+}
+
 .build-logs-view .no-logs {
   color: #8C8C8C;
 }