The type invariation (changing from the real property to the sub items
definition) causes the swagger annotations to end up on the created
`Items` entry.
This changes the behaviour to update the real property entry with the
swagger annotation.
Additionally this ensures that "description", "title" and "example" are
only updated on `Schema` instances.
* support swagger property annotation to descripe properties of model
* support swagger property annotation to descripe properties of model
* fix issues from PR review
* rename method
* remove redundant annotations and revert changes into composer.json
* fix issues from PR comments
* use symfony 3 for default tests
* revert chages
* use symfony 3 for default tests
* revert changes in travis config
