[FIX] import docs: clarify handling of empty cells
[FIX] import docs: clarify handling of empty cells
ovnicraft/openerp-server,MarkusTeufelberger/openobject-server,splbio/openobject-server,ovnicraft/openerp-server,MarkusTeufelberger/openobject-server,gisce/openobject-server,splbio/openobject-server,splbio/openobject-server,gisce/openobject-server,gisce/openobject-server,MarkusTeufelberger/openobject-server