Re-organize directory structure (#4971)

See discussion in #2491

Co-authored-by: Ivan Levkivskyi <ilevkivskyi@dropbox.com>

stdlib/@python2/sys.pyi

@@ -0,0 +1,130 @@
+from types import ClassType, FrameType, ModuleType, TracebackType
+from typing import IO, Any, BinaryIO, Callable, Dict, List, NoReturn, Optional, Sequence, Text, Tuple, Type, Union, overload
+
+# The following type alias are stub-only and do not exist during runtime
+_ExcInfo = Tuple[Type[BaseException], BaseException, TracebackType]
+_OptExcInfo = Union[_ExcInfo, Tuple[None, None, None]]
+
+class _flags:
+    bytes_warning: int
+    debug: int
+    division_new: int
+    division_warning: int
+    dont_write_bytecode: int
+    hash_randomization: int
+    ignore_environment: int
+    inspect: int
+    interactive: int
+    no_site: int
+    no_user_site: int
+    optimize: int
+    py3k_warning: int
+    tabcheck: int
+    unicode: int
+    verbose: int
+
+class _float_info:
+    max: float
+    max_exp: int
+    max_10_exp: int
+    min: float
+    min_exp: int
+    min_10_exp: int
+    dig: int
+    mant_dig: int
+    epsilon: float
+    radix: int
+    rounds: int
+
+class _version_info(Tuple[int, int, int, str, int]):
+    major: int
+    minor: int
+    micro: int
+    releaselevel: str
+    serial: int
+
+_mercurial: Tuple[str, str, str]
+api_version: int
+argv: List[str]
+builtin_module_names: Tuple[str, ...]
+byteorder: str
+copyright: str
+dont_write_bytecode: bool
+exec_prefix: str
+executable: str
+flags: _flags
+float_repr_style: str
+hexversion: int
+long_info: object
+maxint: int
+maxsize: int
+maxunicode: int
+modules: Dict[str, Any]
+path: List[str]
+platform: str
+prefix: str
+py3kwarning: bool
+__stderr__: IO[str]
+__stdin__: IO[str]
+__stdout__: IO[str]
+stderr: IO[str]
+stdin: IO[str]
+stdout: IO[str]
+subversion: Tuple[str, str, str]
+version: str
+warnoptions: object
+float_info: _float_info
+version_info: _version_info
+ps1: str
+ps2: str
+last_type: type
+last_value: BaseException
+last_traceback: TracebackType
+# TODO precise types
+meta_path: List[Any]
+path_hooks: List[Any]
+path_importer_cache: Dict[str, Any]
+displayhook: Callable[[object], Any]
+excepthook: Callable[[Type[BaseException], BaseException, TracebackType], Any]
+exc_type: Optional[type]
+exc_value: Union[BaseException, ClassType]
+exc_traceback: TracebackType
+
+class _WindowsVersionType:
+    major: Any
+    minor: Any
+    build: Any
+    platform: Any
+    service_pack: Any
+    service_pack_major: Any
+    service_pack_minor: Any
+    suite_mask: Any
+    product_type: Any
+
+def getwindowsversion() -> _WindowsVersionType: ...
+def _clear_type_cache() -> None: ...
+def _current_frames() -> Dict[int, FrameType]: ...
+def _getframe(depth: int = ...) -> FrameType: ...
+def call_tracing(fn: Any, args: Any) -> Any: ...
+def __displayhook__(value: object) -> None: ...
+def __excepthook__(type_: type, value: BaseException, traceback: TracebackType) -> None: ...
+def exc_clear() -> None: ...
+def exc_info() -> _OptExcInfo: ...
+
+# sys.exit() accepts an optional argument of anything printable
+def exit(arg: Any = ...) -> NoReturn: ...
+def getcheckinterval() -> int: ...  # deprecated
+def getdefaultencoding() -> str: ...
+def getdlopenflags() -> int: ...
+def getfilesystemencoding() -> str: ...  # In practice, never returns None
+def getrefcount(arg: Any) -> int: ...
+def getrecursionlimit() -> int: ...
+def getsizeof(obj: object, default: int = ...) -> int: ...
+def getprofile() -> Optional[Any]: ...
+def gettrace() -> Optional[Any]: ...
+def setcheckinterval(interval: int) -> None: ...  # deprecated
+def setdlopenflags(n: int) -> None: ...
+def setdefaultencoding(encoding: Text) -> None: ...  # only exists after reload(sys)
+def setprofile(profilefunc: Any) -> None: ...  # TODO type
+def setrecursionlimit(limit: int) -> None: ...
+def settrace(tracefunc: Any) -> None: ...  # TODO type