[cleanup] Few cleanup commit for linting and migrations

[Djailla]

• Remove useless future imports in py3
• cleanup some lint errors

[codecov-commenter]

Codecov Report

Merging #447 into master will decrease coverage by 0.04%.
The diff coverage is 80.00%.

@@            Coverage Diff             @@
##           master     #447      +/-   ##
==========================================
- Coverage   90.80%   90.76%   -0.05%     
==========================================
  Files          44       44              
  Lines        2946     2933      -13     
==========================================
- Hits         2675     2662      -13     
  Misses        271      271              

Impacted Files	Coverage Δ
django_q/brokers/aws_sqs.py	0.00% <ø> (ø)
django_q/brokers/ironmq.py	0.00% <0.00%> (ø)
django_q/brokers/orm.py	97.95% <ø> (ø)
django_q/migrations/0001_initial.py	100.00% <ø> (ø)
django_q/migrations/0002_auto_20150630_1624.py	100.00% <ø> (ø)
django_q/migrations/0003_auto_20150708_1326.py	100.00% <ø> (ø)
django_q/migrations/0004_auto_20150710_1043.py	100.00% <ø> (ø)
django_q/migrations/0005_auto_20150718_1506.py	100.00% <ø> (ø)
django_q/migrations/0006_auto_20150805_1817.py	100.00% <ø> (ø)
django_q/migrations/0007_ormq.py	100.00% <ø> (ø)
... and 11 more

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 142af91...e356018. Read the comment docs.

[Koed00]

Thanks 👍 I started the same thing this morning and I'll gladly incorporate this.
Also updating the code with type hinting and some minor other improvements.
Haven't touched most of this in 5 years.