add relation property mapping

[Gummibeer]

Right now the relation property is missing from the mapping - but the class exists and is working.

[what-the-diff]

• Added a new case to the switch statement
• The new case is for 'relation' type properties
• This will map relation types to Relation class in PropertyFactory::mapTypeToClass() method

[mechelon]

You're absolutely right, thank you! We will merge this for the upcoming release.

[Gummibeer]

It's tagged for v1.0.0 - will this be the next release? Or could you go for a v0.8.1 as it's a fix and I would need that one for a project I'm working on. No real deadline and right now I have adjusted it in vendor - but can't deploy without having a real release.

[johguentner]

It's tagged for v1.0.0 - will this be the next release? Or could you go for a v0.8.1 as it's a fix and I would need that one for a project I'm working on. No real deadline and right now I have adjusted it in vendor - but can't deploy without having a real release.

Thank you for point this out. I'll do a release right now.