Core - Create default instances for properties

UI - Added configurable width/height for brush dialogs

src/Artemis.UI.Shared/Plugins/LayerBrushes/LayerBrushConfigurationDialog.cs

@@ -6,6 +6,18 @@ namespace Artemis.UI.Shared.LayerBrushes
     /// <inheritdoc />
     public class LayerBrushConfigurationDialog<T> : LayerBrushConfigurationDialog where T : BrushConfigurationViewModel
     {
+        /// <inheritdoc />
+        public LayerBrushConfigurationDialog()
+        {
+        }
+
+        /// <inheritdoc />
+        public LayerBrushConfigurationDialog(int dialogWidth, int dialogHeight)
+        {
+            DialogWidth = dialogWidth;
+            DialogHeight = dialogHeight;
+        }
+
         /// <inheritdoc />
         public override Type Type => typeof(T);
     }
@@ -15,6 +27,16 @@ namespace Artemis.UI.Shared.LayerBrushes
     /// </summary>
     public abstract class LayerBrushConfigurationDialog : ILayerBrushConfigurationDialog
     {
+        /// <summary>
+        /// The default width of the dialog
+        /// </summary>
+        public int DialogWidth { get; set; } = 800;
+
+        /// <summary>
+        /// The default height of the dialog
+        /// </summary>
+        public int DialogHeight { get; set; } = 800;
+
         /// <summary>
         ///     The type of view model the tab contains
         /// </summary>