Add a "sales_order" reference to the Build model

- If a build order is made to fulfil a sales order
- Add sales_order filtering to the Build API
- Pass initial information through to the BuildCreate view

InvenTree/build/api.py

@@ -38,6 +38,8 @@ class BuildList(generics.ListCreateAPIView):
     ]
 
     filter_fields = [
+        'part',
+        'sales_order',
     ]
 
     def get_queryset(self):
@@ -48,12 +50,6 @@ class BuildList(generics.ListCreateAPIView):
 
         build_list = super().get_queryset()
 
-        # Filter by part
-        part = self.request.query_params.get('part', None)
-
-        if part is not None:
-            build_list = build_list.filter(part=part)
-
         # Filter by build status?
         status = self.request.query_params.get('status', None)