Refactor much of the new code in log.c
Add new functions: cf_load_strict() and cf_reload_strict() for use by the
server, which does not want to overwrite its in-memory config at all if there
is any defect in the config file. However, commands always want to overwrite
the default in-memory config, even with a defective config file, so that
logging has a chance to succeed.
Added `log_format.dump_config` boolean config option
Upgrade configuration schema macros to allow optional "default label"
argument to SUB_STRUCT and VALUE_SUB_STRUCT elements.
New STRUCT_DEFAULT section declares alternative STRUCT default values
with a label.
If configuration is bad, do not execute commands except those with the
PERMISSIVE_CONFIG property.
Flush log buffer immediately after clearing cf_limbo flag, in case there are no
further log messages that would cause the flush. (Fixes bug that an unrecognised
command produced no log output.)
More block comments in log.c.
Change a test case: configuration options are now case sensitive.
Fix config file load and parse logic in conf.c, always copy 'debug' flags
from config.debug.
The config schema 'interfaces' option is no longer MANDATORY.
Introduce new CLIFLAG_PERMISSIVE_CONFIG to supress bad-config ERROR messages
from the 'config set' and 'config get' commands.
Refactor cli_execute() into cli_parse() and cli_invoke(). Use *const* struct
command_line_option everywhere.
Fix endless recursion if error or debug logged while reading config file
Fix 'config del' logic
Log messages made before log file can be opened are buffered and written
once the file is open
Do not log to file in ANDROID version, just to Android's log system
