Fix definition of ImGui.NET Style structure.

src/ImGui.NET/Align.cs

@@ -1,12 +0,0 @@
-namespace ImGuiNET
-{
-    public enum Align
-    {
-        Left = 1 << 0,
-        Center = 1 << 1,
-        Right = 1 << 2,
-        Top = 1 << 3,
-        VCenter = 1 << 4,
-        Default = Left | Top
-    }
-}

src/ImGui.NET/NativeStyle.cs

@@ -25,7 +25,7 @@ namespace ImGuiNET
         /// <summary>
         /// Alignment for title bar text.
         /// </summary>
-        public Align WindowTitleAlign;
+        public Vector2 WindowTitleAlign;
         /// <summary>
         /// Radius of child window corners rounding. Set to 0.0f to have rectangular windows.
         /// </summary>
@@ -75,6 +75,10 @@ namespace ImGuiNET
         /// </summary>
         public float GrabRounding;
         /// <summary>
+        /// Alignment of button text when button is larger than text. Defaults to (0.5f,0.5f) for horizontally+vertically centered.
+        /// </summary>
+        public Vector2 ButtonTextAlign;
+        /// <summary>
         /// Window positions are clamped to be visible within the display area by at least this amount. Only covers regular windows.
         /// </summary>
         public Vector2 DisplayWindowPadding;

src/ImGui.NET/Style.cs

@@ -50,7 +50,7 @@ namespace ImGuiNET
         /// <summary>
         /// Alignment for title bar text.
         /// </summary>
-        public Align WindowTitleAlign
+        public Vector2 WindowTitleAlign
         {
             get { return _stylePtr->WindowTitleAlign; }
             set { _stylePtr->WindowTitleAlign = value; }