Layer brushes - Added RGB.NET-based layer brushes

Layer brushes - Added sample RGB.NET-based color brush
Layer properties - Save on gradient edit dialog close
Layer properties - Fix layer brush keyframes not working after changing layer brush

src/Artemis.Core/Models/Profile/LayerPropertyGroup.cs

@@ -165,6 +165,9 @@ namespace Artemis.Core.Models.Profile
 
         internal void ApplyToEntity()
         {
+            if (!PropertiesInitialized)
+                return;
+
             // Get all properties with a PropertyDescriptionAttribute
             foreach (var propertyInfo in GetType().GetProperties())
             {