Got message outputs working for ISO cycling.
Removed obsolete ttype flag.
Some tidying.
Fixes for previous.
Fixed a test.

(Verbose validation prints site/user config errors to stderr).
Removed the old message-trigger test.
Added new message trigger tests.
Deleted old message trigger example.
Added a new message trigger example.
Redocumented message triggers.
Removed some debug code.
Removed obsolete cycling flags.
A little more tidying.
Merge pull request #1106 from hjoliver/fix-message-triggers

Fix message triggers for cylc-6