Remove ContentInfo->contentType: API
Remove ContentInfo->contentType: MVC
Remove ContentInfo->contentType: REST
Remove ContentInfo->contentType: Repository
Fixed: removed deprecated properties
Fixed: calling getFieldTypeIdentifier() should not crash the app
Merge branch 'master' into EZP-20400-RemoveContentInfo-ContentType

Conflicts:
	eZ/Publish/Core/MVC/Symfony/Templating/Twig/Extension/ContentExtension.php
Updated ContentExtension tests for ContentInfo->contentType removal
Removed Core ContentInfo, promoted API ContentInfo from abstract to concrete
Merge pull request #218 from ezsystems/EZP-20400-RemoveContentInfo-ContentType

EZP-20400 Remove ContentType from ContentInfo