When a default of '' was specified for TEXT/BLOB columns, the specification
  was silently ignored. This is presumably to be nice to applications (or
  people) who generate their column definitions in a not-very-clever fashion.

  For clarity, doing this now results in a warning, or an error in strict
  mode.


mysql-test/r/federated.result:
  Update results
mysql-test/r/fulltext_distinct.result:
  Update results
mysql-test/r/fulltext_update.result:
  Update results
mysql-test/r/gis-rtree.result:
  Update results
mysql-test/r/gis.result:
  Update results
mysql-test/r/join_outer.result:
  Update results
mysql-test/r/order_by.result:
  Update results
mysql-test/r/type_blob.result:
  Add new results
mysql-test/r/type_ranges.result:
  Update results
mysql-test/t/type_blob.test:
  Add new test
sql/field.cc:
  Issue a warning when setting '' as the default on a BLOB/TEXT column,
  and make it an error in strict mode. Also, clarify comments about when
  NO_DEFAULT_VALUE_FLAG is set.