Improve `exist` validator to support array attributes
Refactoring
Refactoring
Tests updated
Tests updated
MigrateCommand enhancement. `all` option added for `down` action.
CHANGELOG updated
Comments updated
Tests updated
ExistValidator count logic fix
CHANGELOG
CHANGELOG fixed
`allowArray` introduced.
CHANGELOG updated
ExistValidator refactoring
Allow fast finishing
Small changes according to the class reference

It looks like this values are supposed to be in different order due to the class reference and practice.
Merge pull request #3463 from DaSourcerer/travis-ci

[travis-ci] Allow fast finishing
Merge pull request #3464 from it3rmit/patch-4

Small changes according to the class reference
Update various typos and grammar