v0.19.1: Beta release #5

This is a fifth beta release, containing important bugfixes compared to the prior release.

Thanks again to current sponsors: Paweł Zmarzły (pzmarzly), Wesley Moore (wezm), M. Herdiansyah (konimex), q66, saolof, and private sponsors.

With an influx of new features being contributed, a follow-up release is planned. Dinit 0.19.0 was not the final beta after all, and neither will be 0.19.1.

Fixes:

• Resolve issue causing service restarts to hang (affected "bgprocess" and "internal" services).
• Fix handling of "depends-ms.d" service setting (q66).
• Bump protocol version reported by dinit so that full exit status of processes is actually reported (on OSes that support it) (q66).
• dinitcheck warns about non-absolute executable paths in service descriptions (Yao Zi).