Squashed 'maint-travis-ci/' changes from dcbffe2..9bbc15f

9bbc15f use -MDevel::Confess on master testing

git-subtree-dir: maint-travis-ci
git-subtree-split: 9bbc15fd277c0698bf69d143e52ed193b13bdaa6
Synchronise git subtree maint-travis-ci
Make mantissa conditionally optional
Update generated files