correct bug with empty table

SCRUM
BUG
correct wrong code in group_concat

into eagle.mysql.r18.ru:/home/vva/work/LOADDATA/mysql-4.1

version is '-log', '-debug' etc.

into narttu.mysql.fi:/my/mysql-4.1

into the binlog), SLAVE START -> START SLAVE, error test changes.

into mysql.com:/home/mysql_src/mysql-4.1

now by default, FLUSH, OPTIMIZE, ANALYZE, REPAIR commands are written to the
binlog, unless the new NO_WRITE_TO_BINLOG keyword was used :
OPTIMIZE NO_WRITE_TO_BINLOG table t;

Previously these commands were never written to the binlog, but there are
2 reasons to change this :
- the RENAME TABLE in MERGE table bug (#175) on slave
- the possible "differently optimised queries may lead to different
updates on the master and slave" bug, until we have automatic ORDER BY.

FLUSH LOGS/SLAVE/MASTER/TABLES WITH READ LOCK are never written to the binlog.
New test for the new logging behaviour.
Other small change : reload_acl_and_cache() and reset_slave() don't send their errors themselves,
this is more usual.

into narttu.mysql.fi:/my/mysql-4.1

  ./configure --with-charset=big5  didn't work

into narttu.mysql.fi:/my/mysql-4.1

new test for this.

Allow syntax CREATE TABLE t1 (LIKE t2)

into mashka.mysql.fi:/home/my/mysql-4.1

Fixed memory leak in new filesort code
Optimzed sub selects to use keys with outer references.
Increased max tables in join to 62

into serg.mylan:/usr/home/serg/Abk/mysql-4.1

into sinisa.nasamreza.org:/mnt/work/mysql-4.1

was not properly stored in the buffer.

into deer.mysql.r18.ru:/home/hf/work/mysql-4.1.cursor

Protocol_cursor task
net_field_length definitions trimmed with Monty's suggestions

TMP_TABLE_PARAM.
This involved moving things around in include files.
All tests, including the ones with Valgrind passed.