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Squashed commit of the following:

commit 4dd56fda9dad618b5508e9235b6ec5953236fe3a
Author: Daniel Friesel <derf@finalrewind.org>
Date:   Mon Apr 6 08:30:29 2020 +0200

    run ./Build first

commit 6f31024609bc9e8e5f6101bb4ab7a9edb5ed9089
Author: Daniel Friesel <derf@finalrewind.org>
Date:   Mon Apr 6 08:26:50 2020 +0200

    add cpanfile

commit 443f45d5b18ebb0de321e47e73f493d4527eb4f5
Author: Daniel Friesel <derf@finalrewind.org>
Date:   Mon Apr 6 08:12:29 2020 +0200

    Revert "hm"

    This reverts commit 11f4b1161da25b29e5dd7a17a75eff6e3f7b92f9.

commit 11f4b1161da25b29e5dd7a17a75eff6e3f7b92f9
Author: Daniel Friesel <derf@finalrewind.org>
Date:   Mon Apr 6 08:02:09 2020 +0200

    hm

commit 9a5b2e43ac9c786095092a7320eb86552cf6460a
Author: Daniel Friesel <derf@finalrewind.org>
Date:   Mon Apr 6 07:54:24 2020 +0200

    switch to GitHub actions