ChangeLog

2021-07-27
	Support for libconfig 1.7.3

2021-07-22
	Port PCRE from PCRE3 to new PCRE2. PCRE2 Posix API
	seems to have become a mess in Debian 10 so moved to
	use native PCRE2 API, which will be less confusing
	in the long run anyway. POSIX is still supported as
	before.

2020-08-29
	Warn about settings that are present in the
	configuration file but not in the schema, i.e.
	unknown settings.

2020-07-23
	Changed libconfig to be optionnal. Source needs to
	be compiled with -DCONFIG and linked with -lconfig
	if support is wanted. `conffile_option` is ignored
	(and will be considered illegal command line) if
	libconfig is disabled.

2020-07-19
	Changed *_cl_parse() API: now always returns, 0 on success and
	negative on error (before, it would exit() directly, which
	prevents the caller from picking a different parsing strategy,
	or choosing its exit codes)