v0.17.1: 2nd beta release

This is a 2nd beta release to follow up from 0.17.0. The changes are mostly minor; they include some bug fixes, and some behavioural changes, that are listed below; there are also new options for controlling logging.

New features:

• The console log level, and primary log facility (syslog or logfile) log level, can now be specified via the new "--console-level" and "--log-level" options. See the documentation in the dinit(8) man page.

Changes:

• The log file is opened immediately when starting even as a system manager, if possible. This can make it easier to debug boot issues.
• The working directory for a service is now the directory containing the service description. This can simplify specifying configuration files/script locations etc. Implemented by Daniel Kolesa.
• The env-file (environment) path for a service is now relative to the service directory containing the service description. Implemented by Daniel Kolesa.
• Failure to open the env-file (environment) specified for a service is now treated as a hard error (and will prevent a service starting). Implemented by Mobin Aydinfar.

Fixes:

• A service that restarted too often, too quickly but which was a dependency of another service also set to restart did not trigger the restart limit check; this has been fixed.
• Process services with the smooth-recovery option and with readiness notification did not check that readiness notification was received after a smooth restart.
• Don't report ECONNRESET errors in control connections. These indicate that the client closed the connection (possibly by terminating) and do not need to be reported. This prevents a spurious warning on shutdown.
• Give an error when a service is specified as its own output consumer (avoids crash). Thanks to Mobin Aydinfar.
• A better effort to make the symlink created during a "dinitctl enable" operation actually point to the enabled service. (This has no effect on operation).
• Various command line switches which require an additional argument (eg -d, -l) now check that the argument supplied is now empty.
• configure script improvements/fixes by Mobin Aydinfar, and by Roze061