MAINT: Add pre-commit checks

[mgxd]

To avoid all the times where I forget to run black and then have to fix the commits.

[codecov-commenter]

Codecov Report

Merging #178 (4e812a0) into master (18def1f) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #178   +/-   ##
=======================================
  Coverage   32.55%   32.55%           
=======================================
  Files          44       44           
  Lines        3652     3652           
=======================================
  Hits         1189     1189           
  Misses       2463     2463           

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