FIX ModelAdmin::$model_importers alias support#1216

chillu wants to merge 1 commit intosilverstripe:1.8silverstripe/silverstripe-admin:1.8from

silverstripeltd:pulls/1/modeladmin-csv-modelname-aliassilverstripeltd/silverstripe-admin:pulls/1/modeladmin-csv-modelname-aliasCopy head branch name to clipboard