Merge branch 'master' of github.com:MongoEngine/mongoengine into drop_py2_support

docs/changelog.rst

@@ -8,7 +8,15 @@ Development
 - (Fill this out as you fix issues and develop your features).
 - ATTENTION: Drop support for Python2
 - Add Mongo 4.0 to Travis
+- Improve Queryset.get to avoid confusing MultipleObjectsReturned message in case multiple match are found #630
 - Fixed a bug causing inaccurate query results, while combining ``__raw__`` and regular filters for the same field #2264
+- Add support for the `elemMatch` projection operator in .fields() (e.g BlogPost.objects.fields(elemMatch__comments="test")) #2267
+- DictField validate failed without default connection (bug introduced in 0.19.0) #2239
+- Remove methods deprecated years ago:
+    - name parameter in Field constructor e.g `StringField(name="...")`, was replaced by db_field
+    - Queryset.slave_okay() was deprecated since pymongo3
+    - dropDups was dropped with MongoDB3
+    - ``Queryset._ensure_indexes`` and ``Queryset.ensure_indexes``, the right method to use is ``Document.ensure_indexes``
 
 Changes in 0.19.1
 =================

docs/guide/defining-documents.rst

@@ -555,7 +555,6 @@ There are a few top level defaults for all indexes that can be set::
             'index_background': True,
             'index_cls': False,
             'auto_create_index': True,
-            'index_drop_dups': True,
         }
 
 
@@ -574,11 +573,6 @@ There are a few top level defaults for all indexes that can be set::
     in systems where indexes are managed separately. Disabling this will improve
     performance.
 
-:attr:`index_drop_dups` (Optional)
-    Set the default value for if an index should drop duplicates
-    Since MongoDB 3.0 drop_dups is not supported anymore. Raises a Warning
-    and has no effect
-
 
 Compound Indexes and Indexing sub documents
 -------------------------------------------