Merge branch 'patches/pike111' into 8.0

* patches/pike111:
  Sql.mysql / Mysql.SqlTable: Use UTF-8 encoded UTF-16 in a couple of other applicable cases.
  Sql.mysql: Use/support UTF-8 encoded UTF-16.
  Testsuite [utf8_to_string]: Fixed typo.
  EFUNs: Support encoding to UTF-8 encoded UTF-16 in string_to_utf8().