Added several new constants.

modules/cloudsim/src/main/java/org/cloudbus/cloudsim/Consts.java

@@ -9,10 +9,26 @@ package org.cloudbus.cloudsim;
  */
 public final class Consts {
 
-    /**
-     * Suppreses intantiation.
-     */
-    private Consts(){}
+    /** Suppreses intantiation. */
+    private Consts() {
+    }
 
+    /** One million. */
     public static int MILLION = 1000000;
+
+    // ================== Time constants ==================
+    /** One minute time in seconds. */
+    public static int MINUTE = 60;
+    /** One hour time in seconds. */
+    public static int HOUR = 60 * MINUTE;
+    /** One day time in seconds. */
+    public static int DAY = 24 * HOUR;
+    /** One week time in seconds. */
+    public static int WEEK = 24 * HOUR;
+
+    // ================== OS constants ==================
+    /** Constant for *nix OS-es. */
+    public static final String NIX_OS = "Linux/Unix";
+    /** Constant for Windows OS-es. */
+    public static final String WINDOWS = "Windows";
 }