web: '/' only focuses searchbox if it wasn't yet in focus

Fixes #109 

Change-Id: I158c10409cc9a370c83fc2167e36826b3516cf44
diff --git a/web/templates.go b/web/templates.go
index a91f4a9..5f1adec 100644
--- a/web/templates.go
+++ b/web/templates.go
@@ -139,8 +139,11 @@
 document.onkeydown=function(e){
   var e = e || window.event;
   if (e.key == "/") {
-    document.getElementById("navsearchbox").focus();
-    return false;
+    var navbox = document.getElementById("navsearchbox");
+    if (document.activeElement !== navbox) {
+      navbox.focus();
+      return false;
+    }
   }
 };
 </script>