Fix handling of non-uint8 images for PIL imsave.

Fix handling of non-uint8 imags for PIL imsave.

Update build requirements and documentation

Reorganized dependencies in DEPENDS.txt.

Fix install_requires string formatting

Use img_as_ubyte instead of the previous hack

Add to the docstring notes.

Add to docstring notes

Fix errant changes

Add support for tif floating point and 16bit files

Handle case where format_str is None

Add note about 2D TIFF file support

Add handling for uint16 and integer types.
Add tifffile.py and its license.

Add use of tifffile and its license

Actually add the tifffile file and LICENSE
Add tests for new behavior.

Add tests for new behavior

Fix utils import and make io.tests a package
Remove old tifffile plugin in favor of using it in PIL plugin.
Add tifffile.c and associated build target.
Clean up tests and add to bento.info.

Remove "no plugin" test because we will always have a plugin.

Fix handling of bools in ubyte check

Fix integration of tifffile.c

Clean up new tests.

Fix _tifffile import and add to bento.info

Add tifffile.py and fix pil_plugin import

Add tifffile tests to test_pil and remove PIL import checks
Fix PIL tests, move helpers to _shared, fix widgets test
Fix deprecation warning in draw.py from numpy 1.9
Ignore tifffile.py in coveragerc
Reinstate tifffile_plugin for backwards compatibility
Remove temporary file and clean up imports
Reinstate tifffile test
Clean up imsave behavior and beef up docstring
Add references in docstrings
Properly handle all image types for PNG, beef up docs
Fix handling of temp file removal
Fix reference citation
Do not try and save signed integer output, improved signed checks for tif.
Fix docstring typo
Rename the convenience methods