g13gui: bitwidgets: Adding a Rectangle class

So we can draw nice looking rects with curvy corners.

g13gui/g13gui/bitwidgets/rectangle.py

@@ -0,0 +1,27 @@
+from g13gui.bitwidgets.widget import Widget
+
+
+class Rectangle(Widget):
+    def __init__(self, x, y, w, h, radius=0, fill=True):
+        Widget.__init__(self)
+        self.position = (x, y)
+        self.bounds = (w, h)
+        self.radius = radius
+        self.fill = fill
+
+    def draw(self, ctx):
+        if self._visible:
+            points = (self._position[0], self._position[1],
+                      self._position[0] + self._bounds[0],
+                      self._position[1] + self._bounds[1])
+            ctx.rounded_rectangle(*points,
+                                  radius=self._radius,
+                                  fill=self._fill)
+
+    @property
+    def radius(self):
+        return self._radius
+
+    @radius.setter
+    def radius(self, radius):
+        self._setProperty('radius', radius)