Add HarvestProject.deleted flag to track deletions in Harvest

set this flag instead of deleting project, so we do not lose other
info about it.  can delete manually if truly unwanted

rattail_harvest/importing/harvest.py

@@ -28,6 +28,8 @@ import datetime
 import decimal
 import logging
 
+import sqlalchemy as sa
+
 from rattail import importing
 from rattail.util import OrderedDict
 from rattail_harvest import importing as rattail_harvest_importing
@@ -126,6 +128,22 @@ class HarvestProjectImporter(FromHarvest, rattail_harvest_importing.model.Harves
     Import project data from Harvest
     """
 
+    @property
+    def supported_fields(self):
+        fields = list(super(HarvestProjectImporter, self).supported_fields)
+
+        # this is for local tracking only; is not in harvest
+        fields.remove('deleted')
+
+        return fields
+
+    def cache_query(self):
+        model = self.model
+        return self.session.query(model.HarvestProject)\
+                           .filter(sa.or_(
+                               model.HarvestProject.deleted == False,
+                               model.HarvestProject.deleted == None))
+
     def get_host_objects(self):
         return self.webapi.get_projects()['projects']
 
@@ -168,6 +186,13 @@ class HarvestProjectImporter(FromHarvest, rattail_harvest_importing.model.Harves
 
         return data
 
+    def can_delete_object(self, project, data):
+        return not project.deleted
+
+    def delete_object(self, project):
+        project.deleted = True
+        return True
+
 
 class HarvestTaskImporter(FromHarvest, rattail_harvest_importing.model.HarvestTaskImporter):
     """