ctdb-common: Use Samba's DEBUG_FILE logging
This has support for log rotation (or re-opening).
The log format is updated to use an RFC5424 timestamp and to include a
hostname. The addition of the hostname allows trivial merging of log
files from multiple cluster nodes.
The hostname is faked from the CTDB_BASE environment variable during
testing, as per the comment in the code. It is currently faked in a
similar manner in local_daemons.sh when printing logs, so drop this.
Unit tests need updating because stderr logging no longer produces a
"PROGNAME[PID]: " header.
Signed-off-by: Martin Schwenke <martin@meltin.net>
Reviewed-by: Amitay Isaacs <amitay@gmail.com>