Merge tag 'sparks-1.6.9' into develop

1.6.9
Merge tag 'sparks-1.6.9.1' into develop

1.6.9.1
Merge tag 'sparks-1.6.9.2' into develop

1.6.9.2
Try to install `python3` on Ubuntu, this will help when `python3.3` isn't available.
bump version in setup.py
Merge branch 'release/1.6.10'