Support foreign keys.
Add a --list-tables option to list tables that will be modified.
Bug fix - fixed undefined value in duplicate field error message, M::D::Table.

RT 77002: lib/MySQL/Diff/Table.pm was improperly reporting the table
name when throwing an exception related to their being duplicate
field/column names during the parsing of the SQL table definition.

Fixed reference to object instance field and create a unit test to
check for regressions.