remove unused type constraint

it's also using the old form of enum, which is being deprecated
remove another unused file
update dist.ini
update .travis.yml
fix changelog header
require Form::Sensible for smoke testing
changelog
changelog
remove Class::MOP::load_class

use of load_class is deprecated within Moose, removing entirely in favor of
Module::Runtime

Signed-off-by: Caleb Cushing <xenoterracide@gmail.com>