Added window which shows DllManipulatorEditor

Also fixed .gitignore on this branch

Author: mcpiroman

.gitignore

@@ -1 +1 @@
-.meta
+*.meta

src/Editor/DllManipulatorWindowEditor.cs

@@ -0,0 +1,37 @@
+using System.Linq;
+using UnityEngine;
+using UnityEditor;
+
+namespace DllManipulator
+{
+    public class DllManipulatorWindowEditor : EditorWindow
+    {
+        [MenuItem("UnityNativeTool/DLL Manipulator")]
+        static void Init()
+        {
+            var window = GetWindow<DllManipulatorWindowEditor>();
+            window.Show();
+        }
+
+        void OnGUI()
+        {
+            var dllManipulator = FindObjectOfType<DllManipulator>();
+            if (dllManipulator == null)
+            {
+                dllManipulator = Resources.FindObjectsOfTypeAll<DllManipulator>()
+                    .FirstOrDefault(d => !EditorUtility.IsPersistent(d) && d.gameObject.scene.IsValid());
+            }
+
+            if (dllManipulator != null)
+            {
+                var editor = Editor.CreateEditor(dllManipulator);
+                editor.OnInspectorGUI();
+            }
+            else
+            {
+                EditorGUILayout.Space();
+                EditorGUILayout.LabelField($"There is no {nameof(DllManipulator)} script in the scene.");
+            }
+        }
+    }
+}