Fixing 10.16 panel images bug.

Clocker/Overall App/Themer.swift

@@ -448,13 +448,12 @@ extension Themer {
     func symbolImage(for name: String) -> NSImage {
         assert(name.count > 0)
 
-        return NSImage(named: NSImage.Name("Calendar Tab Icon"))!
-//        if #available(OSX 10.16, *) {
-//            return NSImage(systemSymbolName: name,
-//                           accessibilityDescription: name)!
-//        } else {
-//            // Dummy image for older xcodes
-//            return NSImage(named: NSImage.Name("Calendar Tab Icon"))!
-//        }
+        if #available(OSX 10.16, *) {
+            return NSImage(systemSymbolName: name,
+                           accessibilityDescription: name)!
+        } else {
+            // Dummy image for older xcodes
+            return NSImage(named: NSImage.Name("Calendar Tab Icon"))!
+        }
     }
 }