Produce DDL for MySQL table field with ref in 'ON UPDATE'
Fix warning due uninitialized var

"Use of uninitialized value in concatenation"
Add Changes entries for 6c77378 and 1fb4f40
Fix handling of views in MySQL DBI parser

SHOW TABLES and SHOW CREATE TABLE return views too, and Parser::MySQL
handles them just fine, so just pass them on.
Install XML::Parser in Travis, it's used by t/05bgep-re.t
Test Parser::DBI::PostgreSQL in Travis
Set all the env variables in one "env" entry
Switch t/13schema.t to done_testing
Test Schema::Table->is_trivial_link and ->is_data
Install Graph::Directed and GD to test Producer::Diagram
Output the build log on cpanm failure
Install the libgd development package
Ignore Devel::Cover output
Use a schema with FKs for diagram testing
Fix and extend link table tests
Add 'use warnings', test case-insensitive ->get_field