added caching duration referene through the global cache registry implmentation

git-svn-id: https://svn.wso2.org/repos/wso2/carbon/platform/trunk@179281 a5903396-d722-0410-b921-86c7d4935375
scim skips the internal roles of user

git-svn-id: https://svn.wso2.org/repos/wso2/carbon/platform/trunk@179282 a5903396-d722-0410-b921-86c7d4935375