Vladislav

Added Preview attribute size and align arguments. Size was in [NaughtyAttributes](https://dbrizov.github.io/na-docs/attributes/drawer_attributes/show_asset_preview.html) and it was aligned differently. Fixed exception if [Preview] attrubute used in generic class and object of generic class...

I added support for Button label change with LabelText attribute. Updated ButtonSample.cs and in inspector it looks like this:  ```csharp using System.Text; using UnityEngine; using Alchemy.Inspector; namespace Alchemy.Samples {...

Was working with SerializeReference and noticed that I can't copy-paste data which is annoying. Previously I was using Mackysoft Unity-SerializeReferenceExtensions which has copy-paste support and was made to serialize references...