Fix compilation on Windows

[tobiasdiez]

Based on #206, we make cysignals compile nicely on Windows. The tests (that are meaningful for windows) are passing, but I'm not sure if further work is necessary to handle Windows specifics. In either case, this should serve as a good start.

Windows (mingw) is added to ci to make sure that it keeps working.

Fixes #201 and fixes #198

[tobiasdiez]

@dimpase @fchapoton Tests are passing, so this is good to go from my side. Please have a careful look at the changes to make sure I'm not breaking anything on linux and macos here (I really don't have a strong understanding of signal processing on unix).

[dimpase]

you've removed cysignals_config.h.in - are you sure we don't need something like cysignals_config.h ?

[tobiasdiez]

cysignals_config

It's now generated by meson: configure_file(output: 'cysignals_config.h', configuration: config, install_dir: py.get_install_dir(pure: false) / 'cysignals', install: true). No need to have a cysignals_config.h.in as source.

[dimpase]

https://stackoverflow.com/a/8420498/557937 shows how to do a sort of SIGALRM on Windows
(outdated, - python 2.7 - so perhaps there are better ways now)

[dimpase]

It's for a future consideration - this PR doesn't need to do anything here.

[dimpase]

lgtm

[tobiasdiez]

Thanks Dima!