Add deprecation warning to 'data.lena()'

TODO.txt

@@ -13,6 +13,7 @@ Version 0.14
   parameters `(dist, theta)`, LineModelND has the more general parameters
   `(origin, direction)`.
 * Remove deprecated old syntax support for ``skimage.transform.integrate``.
+* Remove deprecated ``skimage.data.lena`` and corresponding data files.
 
 
 Version 0.13
@@ -34,7 +35,6 @@ Version 0.13
   _shared/interpolation.pyx, transform/_geometric.py, and transform/_warps.py
 
 
-
 Version 0.12
 ------------
 * Change `label` to mark background as 0, not -1, which is consistent with

skimage/data/__init__.py

@@ -10,6 +10,7 @@ import os as _os
 
 from .. import data_dir
 from ..io import imread, use_plugin
+from .._shared.utils import deprecated
 from ._binary_blobs import binary_blobs
 
 __all__ = ['load',
@@ -56,6 +57,7 @@ def camera():
     return load("camera.png")
 
 
+@deprecated()
 def lena():
     """Colour "Lena" image.