Nodes - Added gradient nodes

Nodes - Added color gradient pin type
Data bindings - Changed color gradient data bindings to now take a color gradient

src/Artemis.Core/Models/Profile/DataBindings/DataBindingProperty.cs

@@ -35,7 +35,7 @@ public class DataBindingProperty<TProperty> : IDataBindingProperty
     }
 
     /// <inheritdoc />
-    public void SetValue(object? value)
+    public void SetValue(object value)
     {
         // Numeric has a bunch of conversion, this seems the cheapest way to use them :)
         switch (value)

src/Artemis.Core/Models/Profile/DataBindings/IDataBindingProperty.cs

@@ -27,5 +27,5 @@ public interface IDataBindingProperty
     ///     Sets the value of the property this registration points to
     /// </summary>
     /// <param name="value">A value matching the type of <see cref="ValueType" /></param>
-    void SetValue(object? value);
+    void SetValue(object value);
 }