Further fixes

* fixes race condition on geometry conflict calculation if performed in background process
* simplifies access to smaller buffered geometry
* adds mapping of "qm"->"m2" for UnitChoice in API usage for backwards compatibility

api/utils/serializer/v1/intervention.py

@@ -13,7 +13,7 @@ from api.utils.serializer.v1.serializer import AbstractModelAPISerializerV1, \
 from compensation.models import Payment
 from intervention.models import Intervention, Responsibility, Legal, Handler
 from konova.models import Geometry
-from konova.tasks import celery_update_parcels
+from konova.tasks import celery_update_parcels, celery_check_for_geometry_conflicts
 from user.models import UserActionLogEntry
 
 
@@ -165,6 +165,7 @@ class InterventionAPISerializerV1(AbstractModelAPISerializerV1,
         obj.log.add(obj.created)
 
         celery_update_parcels.delay(obj.geometry.id)
+        celery_check_for_geometry_conflicts.delay(obj.geometry.id)
 
         return obj.id