Fixed TSL publisher mapping (#54)

Fixed TSL publisher mapping so that the importer doesn't fail at this phase.

events/importer/tsl.py

@@ -139,7 +139,7 @@ def save_kw(self: 'events.importer.tsl.TslImporter') -> None:
             for k, v in self.keywords.items():
                 kw = Keyword(data_source=getattr(self, 'data_source'))
                 kw.id = k
-                kw.publisher_id = getattr(self, 'organization')
+                kw.publisher = getattr(self, 'organization')
                 for lang, lang_val in v.items():
                     langformat = 'name_%s' % lang
                     setattr(kw, langformat, lang_val)