Update URM Version to 1.4.4 and regenerated all puml files

singleton/etc/singleton.urm.puml

@@ -1,38 +1,39 @@
 @startuml
 package com.iluwatar.singleton {
   class App {
+    - LOGGER : Logger {static}
     + App()
     + main(args : String[]) {static}
   }
-  class ThreadSafeLazyLoadedIvoryTower {
-    - instance : ThreadSafeLazyLoadedIvoryTower {static}
-    - ThreadSafeLazyLoadedIvoryTower()
-    + getInstance() : ThreadSafeLazyLoadedIvoryTower {static}
-  }
-  class InitializingOnDemandHolderIdiom {
-    - InitializingOnDemandHolderIdiom()
-    + getInstance() : InitializingOnDemandHolderIdiom {static}
-  }
-  class ThreadSafeDoubleCheckLocking {
-    - instance : ThreadSafeDoubleCheckLocking {static}
-    - ThreadSafeDoubleCheckLocking()
-    + getInstance() : ThreadSafeDoubleCheckLocking {static}
-  }
-  class IvoryTower {
-    - INSTANCE : IvoryTower {static}
-    - IvoryTower()
-    + getInstance() : IvoryTower {static}
-  }
-  -class HelperHolder {
-    - INSTANCE : InitializingOnDemandHolderIdiom {static}
-    - HelperHolder()
-  }
   enum EnumIvoryTower {
     + INSTANCE {static}
     + toString() : String
     + valueOf(name : String) : EnumIvoryTower {static}
     + values() : EnumIvoryTower[] {static}
   }
+  class InitializingOnDemandHolderIdiom {
+    - InitializingOnDemandHolderIdiom()
+    + getInstance() : InitializingOnDemandHolderIdiom {static}
+  }
+  -class HelperHolder {
+    - INSTANCE : InitializingOnDemandHolderIdiom {static}
+    - HelperHolder()
+  }
+  class IvoryTower {
+    - INSTANCE : IvoryTower {static}
+    - IvoryTower()
+    + getInstance() : IvoryTower {static}
+  }
+  class ThreadSafeDoubleCheckLocking {
+    - instance : ThreadSafeDoubleCheckLocking {static}
+    - ThreadSafeDoubleCheckLocking()
+    + getInstance() : ThreadSafeDoubleCheckLocking {static}
+  }
+  class ThreadSafeLazyLoadedIvoryTower {
+    - instance : ThreadSafeLazyLoadedIvoryTower {static}
+    - ThreadSafeLazyLoadedIvoryTower()
+    + getInstance() : ThreadSafeLazyLoadedIvoryTower {static}
+  }
 }
 IvoryTower -->  "-INSTANCE" IvoryTower
 ThreadSafeDoubleCheckLocking -->  "-instance" ThreadSafeDoubleCheckLocking