/// <summary>
 /// Caching constructor
 /// </summary>
 /// <param name="action">Add/Remove caching action.</param>
 /// <param name="expiration">Expiration of caching value.</param>
 public CachingInterceptorAttribute(CachingAction action, TimeSpan expiration)
 {
     this.Initialize();
     _action     = CachingAction.Add;
     _expiration = expiration;
 }
 /// <summary>
 /// Caching for 15 minutes.
 /// </summary>
 /// <param name="action">Add/Remove caching action.</param>
 public CachingInterceptorAttribute(CachingAction action)
 {
     this.Initialize();
     _action     = CachingAction.Add;
     _expiration = new TimeSpan(0, 15, 0);
 }