setup
Added support for different illuminants.
Added new tests. The support for a wider range of illuminants is now tested.
Added tests for the new functionality.
Undone change in skimage/__init__.py.
The format strings were updated to include numbers.
Corrected code to conform to Python coding conventions (PEP 8).

Added test code for handling exceptions.

Corrected test code to use the full path to the test data.
Added Stephan comments.

Syntax is now checked using `flake8`.
BUG: add signed flag to chars

Sign of char is undefined and there are numerous places where its sign
is important. Fixes tests with -funsigned-char.
Closes gh-1110
DOC: introduce variable num_peaks for reusability
Merge pull request #1136 from juliantaylor/signed-char

BUG: add signed flag to chars
Merge pull request #1137 from sciunto/doc

DOC: introduce variable num_peaks for reusability
add CheckBox widget to viewer.  fix ComboBox widget docstring
added tv_denoise.py viewer example using the CheckBox
fix image scaling in tv_denoise.py example
Clear the blit background when the image changes
Removed the print statements from the test code.
Merge pull request #1144 from blink1073/master

Clear the blit background when the image changes
Incorporated Stefan's comments.
Update find_contours docstring to use r/c notation

This update fixes #1140.

Other docstrings will probably need to be updated as well.