Add initial Rattail -> CORE-POS export logic

only allows "update" for Vendor model so far.  more to come after testing...

rattail_corepos/commands.py

@@ -30,6 +30,23 @@ from rattail import commands
 from rattail.util import load_object
 
 
+class ExportCore(commands.ImportSubcommand):
+    """
+    Export data from Rattail to CORE-POS
+    """
+    name = 'export-corepos'
+    description = __doc__.strip()
+    default_handler_spec = 'rattail_corepos.corepos.importing.rattail:FromRattailToCore'
+
+    def get_handler_factory(self, **kwargs):
+        if self.config:
+            spec = self.config.get('rattail.exporting', 'corepos.handler',
+                                   default=self.default_handler_spec)
+        else:
+            spec = self.default_handler_spec
+        return load_object(spec)
+
+
 class ImportCOREPOS(commands.ImportSubcommand):
     """
     Import data from a CORE POS database