Docs: Use or as separators

[0xGabi]

@bpierre I wonder if maybe we should use or as we did in a few places.

[codecov]

Codecov Report

Merging #118 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #118   +/-   ##
=======================================
  Coverage   24.12%   24.12%           
=======================================
  Files          59       59           
  Lines        1032     1032           
  Branches      167      167           
=======================================
  Hits          249      249           
  Misses        783      783           

Flag	Coverage Δ
#unittests	24.12% <ø> (ø)

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[bpierre]

@bpierre I wonder if maybe we should use or as we did in a few places.

Yes let’s do this! We were talking with @sohkai about perhaps defining somewhere this pseudo language we use to define the types in the documentation (e.g. “How to read this documentation” in the intro page).