Add a user guide to migrate from GSC to EC. covered by: hiroshi_ito.dca
Add a user guide to migrate from GSC to EC. covered by: hiroshi_ito.dca

gs-rezaem/reladomo,gs-rezaem/reladomo,goldmansachs/reladomo,gs-rezaem/reladomo,nikhilnanivadekar/reladomo,gs-rezaem/reladomo,goldmansachs/reladomo,goldmansachs/reladomo,nikhilnanivadekar/reladomo,goldmansachs/reladomo,nikhilnanivadekar/reladomo,gs-rezaem/reladomo,nikhilnanivadekar/reladomo,goldmansachs/reladomo,nikhilnanivadekar/reladomo