add coverage workflow

[danieleades]

adds a coverage workflow using tarpauling and codecov.io

this will require setting up a codecov account to work (using github 0auth2)

[codecov-commenter]

Codecov Report

❗ No coverage uploaded for pull request base (master@8092fc0). Click here to learn what that means.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master     #261   +/-   ##
=========================================
  Coverage          ?   74.80%           
=========================================
  Files             ?       49           
  Lines             ?     2624           
  Branches          ?        0           
=========================================
  Hits              ?     1963           
  Misses            ?      661           
  Partials          ?        0           

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[matthiasbeyer]

I am not sure whether we want this (a codecov account). At least I do not, at this time.

[danieleades]

I am not sure whether we want this (a codecov account). At least I do not, at this time.

i understand the sentiment. It's not a painful process- it's a one-time login using github 0Auth and then it can access and comment on public repos without further setup or authentication. And the reports are quite nice...

shall i close this?

[matthiasbeyer]

Leave it open, my opinion might change in the near future 😆

[epage]

Superseded by #585