Adding RememberMe SessionTimeout config for OpenID

git-svn-id: https://svn.wso2.org/repos/wso2/carbon/platform/trunk@173629 a5903396-d722-0410-b921-86c7d4935375
Adding OpenID.SessionTimeout constant

git-svn-id: https://svn.wso2.org/repos/wso2/carbon/platform/trunk@173630 a5903396-d722-0410-b921-86c7d4935375