[WIP] Implement built-in vars()

[jerivas]

Work in progress.

The class test is an expected failure because type doesn't implement __dict__ in Batavia.

Currently the noargs test is failing because Batavia's locals() output is not the same as Python's:

>>> f = vars
>>> x = "_noargs (should not be use)"
>>> f()
Batavia: {'__builtins__': [object Object], '__name__': '__main__', '__doc__': None, '__package__': None, 'f': function () { [native code] }, 'x': '_noargs (should not be use)'}
Python 3.5: {'x': '_noargs (should not be use)', '__loader__': <_frozen_importlib_external.SourceFileLoader object at 0xXXXXXXXX>, '__doc__': None, '__file__': ***EXECUTABLE***, 'f': <built-in function vars>, '__builtins__': <module 'builtins' (built-in)>, '__name__': '__main__', '__cached__': None, '__spec__': None, '__package__': None}

Part of #47.

PR Checklist:

• All new features have been tested
• All new features have been documented
• I have read the CONTRIBUTING.md file
• I will abide by the code of conduct

[phildini]

Hi there! It looks like this PR might be dead, so we're closing it for now. Feel free to re-open it if you'd like to continue, or think about directing your efforts to https://github.com/beeware/briefcase or https://github.com/beeware/toga. Both of these have more active development right now. 😄