This patch changes the main name of 3 byte character set from utf8 to
utf8mb3. New old_mode UTF8_IS_UTF8MB3 is added and set TRUE by default,
so that utf8 would mean utf8mb3. If not set, utf8 would mean utf8mb4.
for general use.
mysql-test/Makefile.am:
Adding directories of additional test suites
mysql-test/mysql-stress-test.pl:
Adding check for additional errors checking during test run