Added FutureWarning - save will default to cascade=False in 0.8

docs/changelog.rst

@@ -4,6 +4,7 @@ Changelog
 
 Changes in 0.7.X
 =================
+- Added FutureWarning - save will default to `cascade=False` in 0.8
 - Added example of indexing embedded document fields (MongoEngine/mongoengine#75)
 - Fixed ImageField resizing when forcing size (MongoEngine/mongoengine#80)
 - Add flexibility for fields handling bad data (MongoEngine/mongoengine#78)
@@ -99,7 +100,7 @@ Changes in 0.6.8
 ================
 - Fixed FileField losing reference when no default set
 - Removed possible race condition from FileField (grid_file)
-- Added assignment to save, can now do: b = MyDoc(**kwargs).save()
+- Added assignment to save, can now do: `b = MyDoc(**kwargs).save()`
 - Added support for pull operations on nested EmbeddedDocuments
 - Added support for choices with GenericReferenceFields
 - Added support for choices with GenericEmbeddedDocumentFields

docs/upgrade.rst

@@ -2,6 +2,20 @@
 Upgrading
 =========
 
+0.6 to 0.7
+==========
+
+Saves will raise a `FutureWarning` if they cascade and cascade hasn't been set to
+True.  This is because in 0.8 it will default to False.  If you require cascading
+saves then either set it in the `meta` or pass via `save` ::
+
+    # At the class level:
+    class Person(Document):
+        meta = {'cascade': True}
+
+    # Or in code:
+    my_document.save(cascade=True)
+
 0.5 to 0.6
 ==========