Adding Carbon to the requires
Added composer to the tests bootstrap
Chaged the database DateTimeType so it creates Carbon objects
Fixing failing tests in the Database namespace
Fixed Remaining failing tests
Fixating now() for all tests, adding composer to travis
CS fixes
FIxed more CS errors
Added missing MissingModelException class.
Updated docblock and changed return type for Controller::constructClasses()
Show model type in MissingModelException message.
Merge pull request #3328 from cakephp/3.0-carbon

3.0 - Replace the DateTime object
Merge pull request #3338 from ADmad/3.0-misc

3.0 misc