Ensure that all clients reads the appropriate 'client', client-mariadb and 'mariadb' sections from my.cnf
The mysqld server and all clients now reads the new client-server section
Fixed that mysqldumpslow supports new slow log formats and new mysqld --slow- options


client/mysql.cc:
  Read also client-server and client-mariadb sections.
client/mysql_upgrade.c:
  Read also client-server and client-mariadb sections.
client/mysqladmin.cc:
  Read also client-server and client-mariadb sections.
client/mysqlbinlog.cc:
  Read also client-server and client-mariadb sections.
client/mysqlcheck.c:
  Read also client-server and client-mariadb sections.
client/mysqldump.c:
  Read also client-server and client-mariadb sections.
client/mysqlimport.c:
  Read also client-server and client-mariadb sections.
client/mysqlshow.c:
  Read also client-server and client-mariadb sections.
client/mysqltest.cc:
  Read also client-server and client-mariadb sections.
extra/my_print_defaults.c:
  Updated help text
scripts/mysql_fix_privilege_tables.sh:
  Read also sections client client-server client-mariadb
scripts/mysql_install_db.pl.in:
  Also allow --data=* option
  Read also groups mariadb, server and client-server.
scripts/mysql_install_db.sh:
  Also allow --data=* option
  Read also groups mariadb, server and client-server.
  Added --lose-skip-pbxt to bootstrap
scripts/mysql_secure_installation.sh:
  Read also groups client-server and client-mariadb
scripts/mysqld_multi.sh:
  Read also group mariadb
scripts/mysqld_safe.sh:
  Read also groups mariadb server and client-server
scripts/mysqldumpslow.sh:
  Fixed to support new slow log formats
  Added sorting on -ae (aggregated number of retreived rows) and e (retrieved rows)
  Read also group 'mariadb'
  If there is many instances of same option, use last one.
  Get slow log file from options log-slow-queries=filename or query-log-file=filename
  Added support for future --log-basename option
sql-common/client.c:
  Read also groups 'client-server' and 'client-mariadb'
tests/mysql_client_test.c:
  Read also groups 'client-server' and 'client-mariadb'
tests/thread_test.c:
  Read also groups 'client-server' and 'client-mariadb'