Imageio

This release introduces a new plugin based on Pillow, which will take care of
the "common formats" like PNG and JPEG, which was previously the role of the
FreeImage plugin. The latter is still available but the FreeImage library
is no longer distributed by default.

* New Pillow plugin to privide the common formats.
* FreeImage plugin gets lower priority w.r.t. resolving a format.
* No more automatic downloading of libraries and executable (for
FreeImage, FFMPEG and AVBIN plugins).
* Pillow plugin comes with a format to read/write animated GIF to supersede
the one provided by FreeImage.
* Various improvements/fixes to the ffmpeg plugin.
* Fixes and improvements of the DICOM plugin.
* Better support of exr images via FreeImage (by Joel Nises).
* New FEI format (for images produced by the FEI SEM microscope).

* Got rid of Lena image because it can be regarded offensive and is not (explicitly) publicly licensed.
* Fix issue with ffmpeg reader being slow on particular systems (152).
* Tiff plugin updated.
* Add Tiff resolution support (Antony Lee).
* Support for 16bit PNG's (150, by OrganicIrradiation).
* Fixes to ffmpeg plugin (149, 145, 129).
* Fix in using IMAGEIO_FREEIMAGE_LIB (141, by Radomirs Cirskis)
* Better ffmpeg verbosity and exe detection ( 138, 139, by Tim D. Smith).

* Freeimage conda package (in main channel) is updated and works on all
major OS's.
* Conda install imageio!
* Fix bug where the ffmpeg plugin fails on certain video files (131).
* Fix how dicom uses dcmtk for JPEG compressed files.

* Various improvements to the ffmpeg plugin.
* New tiffile plugin that should support most scientific formats.
* New simpleITK wrapper plugin.
* New gdal plugin.
* Freeimage plugin can load freeimage lib provided by conda.
* Dicom plugin improved handling of compressed files.
* Most plugins adopt lazy loading to keep imageio lean, fast, and scalable.
* We now build wheels for Pypi.
* Travis also tests Python 3.5.

This release features several fixes and small improvements, especially
to the ffmpeg plugin.

* Fix 'FrameTime' in first frame of GIF image (90)
* Fix that writing video could freeze on Windows (84)
* Fix that ffmpeg process was sometimes not closed correctly (79)
* Also protect user from clogging the machine for mvolread (89)
* Better support for platforms other than Win/Linux/OSX (87 )
* Support for reading from webcam on OSX (83, 85)
* Support for dpx via the ffmpeg plugin (81)
* Support for wmv via the ffmpeg plugin (83)
* The ffmpeg plugin allows specifying pixelformat. The new default is
more widely supported (83)
* Allow passing additional arguments to ffmpeg command (83)
* Quality of ffmpeg output now set via quality param instead of bitrate (83)
* Imageio now has a few (documented) environment variables to specify
the locations of plugin libraries/exes (thus preventing them from
being automatically downloaded.

Basically a hotfix release. But some new features were introduced.

* Fixed that pip-installing would put README.md and other files in sys.prefix.
* The used ffmpeg exe can be overridden with an environment variable
'IMAGEIO_FFMPEG_EXE'.
* Relative paths work again.
* FFMPEG plugin moved to correct timeframe when seeking (thanks Zulko)