Merge Python 2 and 3 versions of time.pyi (#1909)

* Use variable annotations
* Replace default values by ellipses
* Remove exceptions from function bodies
* Remove superfluous comments
* Remove superfluous newlines
* Use Optional instead of Union[..., None]
* Replace Union[int, float] by just float

* Make time.pyi (Python 2) more closely resemble the Python 3 stub

* Replace _TIME_TUPLE by TimeTuple
* Reorder imports

* time.pyi: Mark two arguments as optional, mark Unix-only function

* time.pyi (Python 2): Use TimeTuple in NamedTuple and reformat

This makes time.pyi more closely match the Python3 version.

* Merge Python 2 and 3 versions of time.pyi

* Only import SimpleNamespace on Python >= 3.3

* Remove default values from module properties

* Remove Optional from strftime() and asctime()

* accept2dyear was removed in Python 3.3

* Rename TimeTuple to _TimeTuple

stdlib/2/time.pyi

@@ -1,54 +0,0 @@
-"""Stub file for the 'time' module."""
-# See https://docs.python.org/2/library/time.html
-
-from typing import NamedTuple, Tuple, Union, Any, Optional
-
-# ----- variables and constants -----
-accept2dyear = False
-altzone = 0
-daylight = 0
-timezone = 0
-tzname = ...  # type: Tuple[str, str]
-
-class struct_time(NamedTuple('_struct_time',
-                             [('tm_year', int), ('tm_mon', int), ('tm_mday', int),
-                              ('tm_hour', int), ('tm_min', int), ('tm_sec', int),
-                              ('tm_wday', int), ('tm_yday', int), ('tm_isdst', int)])):
-    def __init__(self, o: Tuple[int, int, int,
-                                int, int, int,
-                                int, int, int], _arg: Any = ...) -> None: ...
-    def __new__(cls, o: Tuple[int, int, int,
-                              int, int, int,
-                              int, int, int], _arg: Any = ...) -> struct_time: ...
-
-_TIME_TUPLE = Tuple[int, int, int, int, int, int, int, int, int]
-
-def asctime(t: Union[struct_time, _TIME_TUPLE] = ...) -> str:
-    raise ValueError()
-
-def clock() -> float: ...
-
-def ctime(secs: Optional[float] = ...) -> str:
-    raise ValueError()
-
-def gmtime(secs: Optional[float] = ...) -> struct_time: ...
-
-def localtime(secs: Optional[float] = ...) -> struct_time: ...
-
-def mktime(t: Union[struct_time, _TIME_TUPLE]) -> float:
-    raise OverflowError()
-    raise ValueError()
-
-def sleep(secs: float) -> None: ...
-
-def strftime(format: str, t: Union[struct_time, _TIME_TUPLE] = ...) -> str:
-    raise MemoryError()
-    raise ValueError()
-
-def strptime(string: str, format: str = ...) -> struct_time:
-    raise ValueError()
-
-def time() -> float:
-    raise IOError()
-
-def tzset() -> None: ...