add pwd.pyi

builtins/2.7/pwd.pyi

@@ -0,0 +1,15 @@
+def getpwall() -> list<struct_passwd>
+def getpwnam(name:str) -> struct_passwd
+def getpwuid(uid:int) -> struct_passwd
+
+class struct_passwd(tuple): ...
+    n_fields = ...  # type: int
+    n_sequence_fields = ...  # type: int
+    n_unnamed_fields = ...  # type: int
+    pw_dir = ...  # type: str
+    pw_name = ...  # type: str
+    pw_passwd = ...  # type: str
+    pw_shell = ...  # type: str
+    pw_gecos = ...  # type: str
+    pw_gid = ...  # type: int
+    pw_uid = ...  # type: int