Add `image_label2rgb`
Fix: Add setup.py which adds data file to the build
ENH: Add some checks on the inputs.
TST: Add tests for image_label2rgb
DOC: Change more examples to use `image_label2rgb`
API Change: `image_label2rgb` changed to `label2rgb`.

The name change reflects a switch in the argument order (and makes the image an optional argument).
FEAT: Generalized n-dimensional array padding
This PR exposes NumPy 1.8+ padding functionality to all
users of scikit-image, regardless of their personal NumPy
version.

The improved (much better scaling with dimensionality)
version introduced in NumPy 1.8 is used.
Change color definitions from ini file to python module

This simplifies the code and allows users to use either `color_dict` or module
variables, e.g., `rgb_colors.white`.
Hough transform for ellipses
use memoryview
s/int/long memory view
delete duplicated import
fix imports
remove commented lines
fix import
delete comment
fix import testing
add spaces for travis (pep8)
fix import testing
pep8