Method binding tests for #494.

tests/run/function_binding_T494.pyx

+cimport cython
+
+class SomeNumber(object):
+
+    def __init__(self, n):
+        self._n = n
+    
+    def __repr__(self):
+        return "SomeNumber(%s)" % self._n
+
+@cython.binding(True)
+def add_to_func(self, x):
+    """
+    >>> add_to_func(SomeNumber(2), 5)
+    7
+    >>> SomeNumber(3).add_to(10)
+    13
+    >>> SomeNumber.add_to(SomeNumber(22), 7)
+    29
+    """
+    return self._n + x
+
+@cython.binding(False)
+def new_num(n):
+    """
+    >>> new_num(11)
+    SomeNumber(11)
+    >>> SomeNumber.new(11)
+    SomeNumber(11)
+    >>> SomeNumber(3).new(11)
+    SomeNumber(11)
+    """
+    return SomeNumber(n)
+
+SomeNumber.add_to = add_to_func
+SomeNumber.new = new_num