Minions: Merge Clints repository to yours.

Having the cutscenes and some refactoring at the mainline repository now, this will cause some merge conflicts for the minions. As I did most of the refactoring and I don't want to bring the merge conflicts as your burden, I resolved these merge conflicts. Feel free to resolve them yourself, or taking this version. (Resolving merges is a great thing to learn and is fun, at least for me, sometimes ;)
This pull request is basically the same as clintbellanger#550 However the cutscenes and the refactoring have been integrated into Clints repo with clintbellanger#545

This PR contains a few commits, which are not yet part of the mainline repo:
0b40dc5 Merge remote-tracking branch 'mainline/master' into minions
512da7c Remove unneeded Entity::face
dc153e6 Replace whitespaces by tabs.
12365ec Initialize variables in constructors.