[IMP] tests: add test on related fields
[IMP] tests: add test on related fields
gisce/openobject-server,splbio/openobject-server,MarkusTeufelberger/openobject-server,splbio/openobject-server,ovnicraft/openerp-server,splbio/openobject-server,ovnicraft/openerp-server,MarkusTeufelberger/openobject-server,gisce/openobject-server,gisce/openobject-server,MarkusTeufelberger/openobject-server