2.7 stub updates (#149)

* Stubgen modules for 2.7

Cookie
email._parseaddr
email.utils
genericpath
linecache
mimetypes
multiprocessing
multiprocessing.process
multiprocessing.util
posixpath
quopri
runpy
weakref
wsgiref.validate

* 2.7/typing.py: add missing __contains__ definition

* 2.7/subprocess.py: make output argument to CalledProcessError optional

Commit f08160bd did the same for py3.

* 2.7/hmac.pyi: add compare_digest

This function was introduced to the 2.7 series in 2.7.7.

* Stubgen 2.7/ssl.pyi

This replaces a nearly-empty handwritten stub.

* Copy constants and other definitions from py3 to py2 ssl.pyi

* 2.7/__future__.pyi: add methods

* 2.7/_weakref.pyi: backport some definitions from 3.x version

* Stubgen 2.7/locale.pyi

Hand-edited to remove declarations that are redundant (and cause
conflicts with) the "from _locale import *" line.

stdlib/2.7/wsgiref/validate.pyi

@@ -0,0 +1,47 @@
+# Stubs for wsgiref.validate (Python 2)
+#
+# NOTE: This dynamically typed stub was automatically generated by stubgen.
+
+from typing import Any
+
+class WSGIWarning(Warning): ...
+
+def validator(application): ...
+
+class InputWrapper:
+    input = ... # type: Any
+    def __init__(self, wsgi_input): ...
+    def read(self, *args): ...
+    def readline(self): ...
+    def readlines(self, *args): ...
+    def __iter__(self): ...
+    def close(self): ...
+
+class ErrorWrapper:
+    errors = ... # type: Any
+    def __init__(self, wsgi_errors): ...
+    def write(self, s): ...
+    def flush(self): ...
+    def writelines(self, seq): ...
+    def close(self): ...
+
+class WriteWrapper:
+    writer = ... # type: Any
+    def __init__(self, wsgi_writer): ...
+    def __call__(self, s): ...
+
+class PartialIteratorWrapper:
+    iterator = ... # type: Any
+    def __init__(self, wsgi_iterator): ...
+    def __iter__(self): ...
+
+class IteratorWrapper:
+    original_iterator = ... # type: Any
+    iterator = ... # type: Any
+    closed = ... # type: Any
+    check_start_response = ... # type: Any
+    def __init__(self, wsgi_iterator, check_start_response): ...
+    def __iter__(self): ...
+    def next(self): ...
+    def close(self): ...
+    def __del__(self): ...