Introduce CFINCOMPATIBLE config parse result flag.
Sort interface rules by unsigned integer key.
Legacy and modern 'interfaces' config styles are now incompatible.
Validate config_network_interface struct to enforce that only exactly one of
'match' and 'dummy' options are set.
Add test cases for 'interface' config option.
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
Tests assert that stderr contains no ERROR: lines after a successful exit
Rewrote sqlite_exec_int64() to separate error outcomes from legitimate
result values
Changed several WHY() calls to DEBUG()
Improved test framework
