Integrate `flake8-isort`

[Peque]

Imports are compatible with Black, in case we end-up integrating that tool some day.

Fixes #276.

[codecov[bot]]

Codecov Report

Merging #321 into master will decrease coverage by <.01%. The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #321      +/-   ##
==========================================
- Coverage   99.25%   99.24%   -0.01%     
==========================================
  Files          26       25       -1     
  Lines        3602     3566      -36     
  Branches      261      257       -4     
==========================================
- Hits         3575     3539      -36     
  Misses         15       15              
  Partials       12       12

Impacted Files	Coverage Δ
osbrain/logging.py	100% <ø> (ø)	:arrow_up:
osbrain/tests/common.py	100% <ø> (ø)	:arrow_up:
osbrain/tests/test_agent_sync_publications.py	100% <100%> (ø)	:arrow_up:
osbrain/tests/test_agent_transport.py	96.42% <100%> (ø)	:arrow_up:
osbrain/agent.py	98.17% <100%> (ø)	:arrow_up:
osbrain/tests/test_address.py	100% <100%> (ø)	:arrow_up:
osbrain/nameserver.py	99.21% <100%> (ø)	:arrow_up:
osbrain/tests/test_agent_req_rep.py	100% <100%> (ø)	:arrow_up:
osbrain/tests/test_timer.py	99.02% <100%> (ø)	:arrow_up:
osbrain/tests/test_nameserver.py	98.11% <100%> (ø)	:arrow_up:
... and 14 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 1f9534d...b7e2691. Read the comment docs.

[Peque]

We will wait a bit to see if AppVeyor's Python 3.7 issue is resolved.

[ocaballeror]

@Peque You are just dying to integrate Black :)

Why don't you pull the trigger already and live in peace yourself