Remove contact_type cache CRM-12464

----------------------------------------
* CRM-12464: Search improvements in 4.4
  http://issues.civicrm.org/jira/browse/CRM-12464

CRM/Core/PseudoConstant.php

@@ -224,13 +224,6 @@ class CRM_Core_PseudoConstant {
    */
   private static $extensions;
 
-  /**
-   * contact Type
-   * @var array
-   * @static
-   */
-  private static $contactType;
-
   /**
    * Financial Account Type
    * @var array