Add new operator function names from SQLAlchemy 1.4 (dropbox#237)

sqlalchemy-stubs/sql/operators.pyi

@@ -84,11 +84,15 @@ class ColumnOperators(Operators):
 def from_(): ...
 def as_(): ...
 def exists(): ...
+def is_true(a): ...
 def istrue(a): ...
+def is_false(a): ...
 def isfalse(a): ...
 def is_distinct_from(a, b): ...
+def is_not_distinct_from(a, b): ...
 def isnot_distinct_from(a, b): ...
 def is_(a, b): ...
+def is_not(a, b): ...
 def isnot(a, b): ...
 def collate(a, b): ...
 def op(a, opstring, b): ...
@@ -97,25 +101,33 @@ def notlike_op(a, b, escape: Optional[Any] = ...): ...
 def ilike_op(a, b, escape: Optional[Any] = ...): ...
 def notilike_op(a, b, escape: Optional[Any] = ...): ...
 def between_op(a, b, c, symmetric: bool = ...): ...
+def not_between_op(a, b, c, symmetric: bool = ...): ...
 def notbetween_op(a, b, c, symmetric: bool = ...): ...
 def in_op(a, b): ...
+def not_in_op(a, b): ...
 def notin_op(a, b): ...
 def distinct_op(a): ...
 def any_op(a): ...
 def all_op(a): ...
 def startswith_op(a, b, escape: Optional[Any] = ...): ...
+def not_startswith_op(a, b, escape: Optional[Any] = ...): ...
 def notstartswith_op(a, b, escape: Optional[Any] = ...): ...
 def endswith_op(a, b, escape: Optional[Any] = ...): ...
+def not_endswith_op(a, b, escape: Optional[Any] = ...): ...
 def notendswith_op(a, b, escape: Optional[Any] = ...): ...
 def contains_op(a, b, escape: Optional[Any] = ...): ...
+def not_contains_op(a, b, escape: Optional[Any] = ...): ...
 def notcontains_op(a, b, escape: Optional[Any] = ...): ...
 def match_op(a, b, **kw): ...
+def not_match_op(a, b, **kw): ...
 def notmatch_op(a, b, **kw): ...
 def comma_op(a, b): ...
 def concat_op(a, b): ...
 def desc_op(a): ...
 def asc_op(a): ...
+def nulls_first_op(a): ...
 def nullsfirst_op(a): ...
+def nulls_last_op(a): ...
 def nullslast_op(a): ...
 def json_getitem_op(a, b): ...
 def json_path_getitem_op(a, b): ...