sub-tables are accessed via the MySQL API like the MYSQL CONNECT tables.

modified:
  mysql-test/suite/connect/r/tbl.result
  mysql-test/suite/connect/t/tbl.test
  storage/connect/catalog.h
  storage/connect/ha_connect.cc
  storage/connect/mycat.cc
  storage/connect/mycat.h
  storage/connect/tabmysql.h
  storage/connect/tabtbl.cpp