add tests for adding Vectors

src/fancymath/vector.py

@@ -30,6 +30,12 @@ class Vector(object):
         s = "Vector(x=%s, y=%s, z=%s)" % (self.x, self.y, self.z)
         return s
 
+    def __add__(self, other):
+        x = self.x + other.x
+        y = self.y + other.y
+        z = self.z + other.z
+        return self.__class__(x, y, z)
+
 
 if __name__ == "__main__":
     v1 = Vector(3, 4, 0)