NO_ZERO_IN_DATE, and INVALID_DATES bits of SQL_MODE. (Bug #5906)


include/my_time.h:
  Pass flags to number_to_datetime() so it can check things
  like NO_ZERO_DATE.
libmysql/libmysql.c:
  Enable fuzzy date handling when converting strings and numbers
  to datetime fields.
mysql-test/r/ps_2myisam.result:
  Update results
mysql-test/r/ps_3innodb.result:
  Update results
mysql-test/r/ps_4heap.result:
  Update results
mysql-test/r/ps_5merge.result:
  Update results
mysql-test/r/ps_6bdb.result:
  Update results
mysql-test/r/ps_7ndb.result:
  Update results
mysql-test/r/strict.result:
  Update results
mysql-test/r/timezone2.result:
  Update results
mysql-test/r/type_datetime.result:
  Update results
mysql-test/t/strict.test:
  Add new regression test
mysql-test/t/timezone2.test:
  Add new test of timestamp values in DST gap
sql-common/my_time.c:
  Expand check_date() to check NO_ZERO_DATE and NO_ZERO_IN_DATE, and
  use it from number_to_datetime() as well as str_to_datetime(). Also,
  make number_to_datetime() return -1 on error so we can distinguish
  between a violation of NO_ZERO_DATE and other errors.
sql/field.cc:
  Update conversion of numbers to date, datetime, and timestamp to
  use number_to_datetime() and report errors and warnings correctly
  and consistently.