MAINT: add docker image/circle build

[mgxd]

Closes #68

TODO:

• Test build
• Add docker / twine credentials
• Release

[pull-assistant]

Best reviewed: commit by commit

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Optimal code review plan

     MAINT: add docker image/circle build

     fix: syntax

     Update .circleci/config.yml

     Update .circleci/config.yml

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[codecov-io]

Codecov Report

Merging #80 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master      #80   +/-   ##
=======================================
  Coverage   98.89%   98.89%           
=======================================
  Files          11       11           
  Lines         992      992           
  Branches      129      129           
=======================================
  Hits          981      981           
  Misses          6        6           
  Partials        5        5

Flag	Coverage Δ
#unittests	98.89% <ø> (ø)	⬆️

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[oesteban]

Getting there.

[oesteban]

(I've just added the required credentials)