jeremyevans/sequel — pull request #795 by noah256 (2014-04-11 23:31:52+00:00)
Title: Use foreign key constraint names in MySQL alter table

When using a MySQL adapter to alter a table to add a foreign key and
receiving a `foreign_key_constraint_name` option, use the value of that
option as the constraint name in the generated SQL.

This value is being respected when creating the table, but not in an `ALTER`.