v1.2.0

Changes:
- removed `python -m` from help
  commit 74d402712083e8675d4dd716eeccd754957bc5a8
- run tests with tox
  commit b99ce5773fbe0f8296b87e5868be1c3683e7cab6

Readme:
- tab completion for pipx
  commit d44252231ad8a006f74cd659ef62d9a606e46b5f
- how to do updates
  commit 313ba6ee2b62e2005658a9ba4295f50c2e8158b0

New features:
- gits and gitd support --version
  commit 457459dd6a196b6683af20562bb1d5641cdbedd1