Move Common functionality to Core project & rendering and Model support as well

PckStudio.Core/Interfaces/IModelImportProvider.cs

@@ -0,0 +1,22 @@
+using System;
+using System.IO;
+using PckStudio.Core;
+
+namespace PckStudio.Interfaces
+{
+    public interface IModelImportProvider<T> where T : class
+    {
+        public string Name { get; }
+
+        public FileDialogFilter DialogFilter { get; }
+
+        public bool SupportImport { get; }
+        public bool SupportExport { get; }
+
+        public T Import(string filename);
+        public T Import(Stream stream);
+
+        public void Export(string filename, T model);
+        public void Export(ref Stream stream, T model);
+    }
+}