Make a machine password. Will be used to let the admin user open student files

EduNetworkBuilder/TrippleDESDocumentEncryption.cs

@@ -148,6 +148,10 @@ namespace EduNetworkBuilder
         {
             return GenUserPW(RanGen, NB.DefaultPasswordLen);
         }
+        public static string GenMachinePW(Random RanGen)
+        {
+            return GenUserPW(RanGen, NB.DefaultMachinePasswordLen);
+        }
 
         public static string GenUserPW(Random RanGen, int length)
         {