Minimum sizes make more sense now

object.go

@@ -109,10 +109,11 @@ type Box interface {
 	Window         () Window
 	Bounds         () image.Rectangle
 	InnerBounds    () image.Rectangle
+	MinimumSize    () image.Point
 	SetBounds      (image.Rectangle)
 	SetColor       (color.Color)
 	SetBorder      (...Border)
-	SetMinimumSize (int, int)
+	SetMinimumSize (image.Point)
 	SetPadding     (Inset)
 
 	SetDNDData   (data.Data)
@@ -159,6 +160,8 @@ type ContentBox interface {
 // TextBox is a box that contains text content.
 type TextBox interface {
 	ContentBox
+
+	SetText      (string)
 	SetTextColor (color.Color)
 	SetFace      (font.Face)
 	SetHAlign    (Align)