finish Python 2 -> 3 migration, remove dependecy on Six

[a-detiste]

No description provided.

[a-detiste]

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[tobias-urdin]

@Mergifyio rebase

[mergify]

rebase

✅ Branch has been successfully rebased

[tobias-urdin]

pep8 job error:

./gnocchiclient/utils.py:15:1: I201 Missing newline between import groups. 'from dateutil import tz' is identified as Third Party and 'import urllib.parse' is identified as Stdlib.
from dateutil import tz

let me know if you want to work on this or i'll fix it in the end of the week and add it to the upcoming release

[tobias-urdin]

thanks!