committing custom sequences feature

git-svn-id: https://svn.wso2.org/repos/wso2/carbon/platform/trunk@181232 a5903396-d722-0410-b921-86c7d4935375
Fixing APIMANAGER-1448

git-svn-id: https://svn.wso2.org/repos/wso2/carbon/platform/trunk@181233 a5903396-d722-0410-b921-86c7d4935375