Release script errase dist folder
closes#793
Release can only be done on master branch
closes#829
Update the playground owl version on release
closes#814
Add logError method in release to show messages in red.
Check-formatting command added to the release process.
The reviewer for the commit on named slots inside named slots did not
notice that there was an infinite loop. Because of his sloppiness, Owl
could block in an infinite loop when a named t-slots was defined inside
a subcomponent, but not as a direct child.
Géry Debongnie