Add standard dis tests

There are a number of standard tests which are interesting and should be added:
https://github.com/python/cpython/blob/master/Lib/test/test_dis.py

I also have some tests which from my now abandoned backports.dis project which may be of interest adding:
https://github.com/moagstar/backports.dis/blob/master/src/backports/tests/est_backport_dis.py
