Add warnings for single line inserts. To do this I had to convert count_cuted_fields to an enum (to be able to detect setting a NOT NULL field to NULL)


mysql-test/r/ctype_mb.result:
  update results after adding more warnings
mysql-test/r/null.result:
  update results after adding more warnings
mysql-test/r/select_found.result:
  update results after adding more warnings
mysql-test/r/warnings.result:
  update results after adding more warnings
mysql-test/t/ctype_mb.test:
  Add missing drop table
mysql-test/t/myisam.test:
  Disable some warnings
mysql-test/t/select_found.test:
  update results after adding more warnings
sql/field_conv.cc:
  Add warnings for single line inserts
sql/item_func.cc:
  Remove compile warnings
sql/sql_class.cc:
  Add warnings for single line inserts
sql/sql_class.h:
  Add warnings for single line inserts
sql/sql_insert.cc:
  Add warnings for single line inserts
sql/sql_load.cc:
  Add warnings for single line inserts
sql/sql_select.cc:
  Add warnings for single line inserts
sql/sql_table.cc:
  Add warnings for single line inserts
sql/sql_update.cc:
  Add warnings for single line inserts