Moved the first example of "early binding for speed" in the examples …

…directory for testing.

docs/examples/userguide/early_binding_for_speed/rectangle.pyx

@@ -0,0 +1,19 @@
+cdef class Rectangle:
+    cdef int x0, y0
+    cdef int x1, y1
+
+    def __init__(self, int x0, int y0, int x1, int y1):
+        self.x0 = x0
+        self.y0 = y0
+        self.x1 = x1
+        self.y1 = y1
+
+    def area(self):
+        area = (self.x1 - self.x0) * (self.y1 - self.y0)
+        if area < 0:
+            area = -area
+        return area
+
+def rectArea(x0, y0, x1, y1):
+    rect = Rectangle(x0, y0, x1, y1)
+    return rect.area()

docs/src/userguide/early_binding_for_speed.rst

@@ -22,22 +22,7 @@ use of 'early binding' programming techniques.
 
 For example, consider the following (silly) code example:
 
-.. sourcecode:: cython
-
-    cdef class Rectangle:
-        cdef int x0, y0
-        cdef int x1, y1
-        def __init__(self, int x0, int y0, int x1, int y1):
-            self.x0 = x0; self.y0 = y0; self.x1 = x1; self.y1 = y1
-        def area(self):
-            area = (self.x1 - self.x0) * (self.y1 - self.y0)
-            if area < 0:
-                area = -area
-            return area
-
-    def rectArea(x0, y0, x1, y1):
-        rect = Rectangle(x0, y0, x1, y1)
-        return rect.area()
+.. literalinclude:: ../../examples/userguide/early_binding_for_speed/rectangle.pyx
 
 In the :func:`rectArea` method, the call to :meth:`rect.area` and the
 :meth:`.area` method contain a lot of Python overhead.