Instantiating Objects with interface

[sima995]

Is your feature request related to a problem? Please describe.
Referencing UnityEngine.Object with a specific interface is great, but then trying to instantiating them is unsafe. A cast is required at some point.

Describe the solution you'd like
A reference type where only classes of type UnityEngine.Object are allowed. Getting the value of that reference would always return that type so Instantiate(referencedPrefab.Value) would work straight away.

Maybe an extension method that instantiates the Object and returns the interface?

[Thundernerd]

Fixed in #61