Project: datamanagement
Issue DM-3133: add "dax_" prefix to data access related packages
As agreed at [Data Access Mtg 2015/07/13|https://confluence.lsstcorp.org/display/DM/Data+Access+Meeting+2015-07-13], add dax_ prefix towebserv, webservcommon, webserv_client, dbserv, imgserv, metaserv
Story points: 1