```
$ python3.4
Python 3.4.3 (default, Nov 17 2016, 01:08:31)
[GCC 4.8.4] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> list(filter(None, [False, True]))
[True]
>>>
```
* add stubs for Python 2 profile and cProfile
Partially fixes#531. Contrary to the Python 2.7 docs at
https://docs.python.org/2/library/profile.html#module-cProfile,
these modules do not have exactly the same interface. For
example, profile.Profile() does not have an enable() method.
* profile stubs: move to 2and3, add __init__, use private names for typevars