Setting username and tenantid into carboncontext after authorization.

git-svn-id: https://svn.wso2.org/repos/wso2/carbon/platform/trunk@178665 a5903396-d722-0410-b921-86c7d4935375
Remove user queryparam and read username and tenantid from carboncontext

git-svn-id: https://svn.wso2.org/repos/wso2/carbon/platform/trunk@178666 a5903396-d722-0410-b921-86c7d4935375
made TemplateContext constructor to be public

git-svn-id: https://svn.wso2.org/repos/wso2/carbon/platform/trunk@178667 a5903396-d722-0410-b921-86c7d4935375