random: Make closer to original

We can now use int.from_bytes.
Fix stub of assertRaises

Closes #222.
Support assertRaises as context manager

Closes #223.
Add assertSequenceEqual

Closes #225.
Add dict.fromkeys to stubs

Closes #226.
Add sys.gettotalrefcount

This is in debug builds only. Added because tests for random use it.
Add pickle.load
Add unittest.TestCase methods to stubs

Closes #228.
Add set methods to stubs

Closes #227.
Adapt base64 test cases to static typing
Adapt fnmatch test cases to static typing
Adapt getopt test cases to static typing
Adapt textwrap test cases to static typing
Adapt random test cases to (partial) static typing
Adapt glob test cases to static typing
Fix to shutil stub/lib

Fixes #236.
Minor builtins stub fix
Fixes to unittest stubs

Fixes #237.
Misc changes to incomplete stubs
Update development status