Miscelaneous functions:
LIKE_RANGE_MIN(), LIKE_RANGE_MAX(), WEIGHT_STRING(),
GET_FORMAT(), FORMAT(), LOAD_FILE().

Print default values for BLOB's.
This is a part commit for automatic changes to make the real commit smaller.
All changes here are related to that we now print DEFAULT NULL for blob and
text fields, like we do for all other fields.

Disable IDENTITY_SUBST propagation for ZEROFILL columns,
as discussed with Sergei.

MDEV-6066: Merge new defaults from 5.6 and 5.7 (defaults changed, QC can be stopped with no-zero size)