Add initial CI testing capabilities

[sloede]

Resolves #17.

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (main@8078677). Click here to learn what that means.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main      #19   +/-   ##
=======================================
  Coverage        ?   73.01%           
=======================================
  Files           ?        2           
  Lines           ?       63           
  Branches        ?        0           
=======================================
  Hits            ?       46           
  Misses          ?       17           
  Partials        ?        0           

Flag	Coverage Δ
unittests	73.01% <0.00%> (?)

Flags with carried forward coverage won't be shown. Click here to find out more.

[sloede]

It would be great if you could have a quick look @bgeihe such that you have an idea of what I changed and did here. Right now, we are only doing smoke tests, i.e., I am running the simple example and verify that it does not return with a non-zero exit code.

[sloede]

Oh, and coverage is only covering the non-Julia files at the moment, so this is something to be investigated in the future.

[benegee]

Something great again!

Concerning the coding, I'm lost though.