Logging 500 errors

[AmanuelAaron]

PR is dependant on #33

[codecov-io]

Codecov Report

Merging #35 into master will decrease coverage by 1.57%.
The diff coverage is 27.02%.

@@            Coverage Diff             @@
##           master      #35      +/-   ##
==========================================
- Coverage    89.3%   87.73%   -1.58%     
==========================================
  Files           7        7              
  Lines         823      848      +25     
==========================================
+ Hits          735      744       +9     
- Misses         88      104      +16

Impacted Files	Coverage Δ
tests/test_api.py	97.64% <100%> (+0.07%)	⬆️
nazgul/api.py	75.27% <12.9%> (-4.41%)	⬇️

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[oremj]

Can we look into logging these in JSON format?

[oremj]

I think we should either do it like this: https://docs.python.org/3/howto/logging-cookbook.html#implementing-structured-logging or you could look in to a package like https://github.com/hynek/structlog

[jbuck]

Rather than rolling your own structured logger, I think it'd make more sense to use an existing one like the built-in Flask logger or structlog