first add files

lib/Crypto/Util/Counter.pyi

@@ -0,0 +1,5 @@
+from typing import Optional, Union, Dict
+
+def new(nbits: int, prefix: Optional[bytes]=..., suffix: Optional[bytes]=..., initial_value: Optional[int]=1,
+        little_endian: Optional[bool]=False, allow_wraparound: Optional[bool]=False) -> \
+        Dict[str, Union[int, bytes, bool]]: ...