This adapts the existing in-process logcatcher from tstest/integration
into a public type and uses it on the side of testcontrol. This also
fixes a bug in the Alpine Linux OpenRC unit that makes every value in
`/etc/default/tailscaled` exported into tailscaled's environment, a-la
systemd [Service].EnviromentFile.
Signed-off-by: Christine Dodrill <xe@tailscale.com>
Alpine Linux[1] is a minimal Linux distribution built around musl libc.
It boots very quickly, requires very little ram and is as close as you
can get to an ideal citizen for testing Tailscale on musl. Alpine has a
Tailscale package already[2], but this patch also makes it easier for us
to provide an Alpine Linux package off of pkgs in the future.
Alpine only offers Tailscale on the rolling-release edge branch.
[1]: https://alpinelinux.org/
[2]: https://pkgs.alpinelinux.org/packages?name=tailscale&branch=edge
Updates #1988
Signed-off-by: Christine Dodrill <xe@tailscale.com>
