v2.2.0
* Walk in alphabetical order
* Check code with vulture and radon

v2.1.0
* Remove adv support. It was inferior to other methods anyway.
* Remove jpegrescan support. Inferior to mozjpeg
* Don't preserve ctime/mtime when making new pngs
* Use pytest instead of nosetest
* Require formating with black & isort

v2.0.1
* Pillow 7 compatibility

v2.0.0
* Stop supporting python 2
* Switch to poetry build system
* Type checking with mypy

v1.6.3
* Don't use pngout on 16 bit pngs because it crashes
* Fix broken option -D --optimize_after

v1.6.2
* Fix illegal stack trace call.

v1.6.1
* Fix exception handling when extern process returns non-zero

v1.6.0
* Report on all errors at the end
* Remove PIL support. Pillow only now.
* Python3 proof

v1.5.3
* Fix hang on external program error. Especially likley with 16 bit PNGs and pngout.

v1.5.2
* Additional compatibility with Python 3
* Fix formats as a list when it should be a set issue

v1.5.1
* Drop TIFF support. It was never a good idea, tiff is usually a metadata store. And behaves poorly with older optipng.
* Fix space savings reporting bug where savings always equaled zero

v1.4.5
* When setting new timestamps, don't remove timestamps above the root paths specified as input

v1.4.4
* Use timestamp cacheing more often

v1.4.3
* Fix bug where files would sometimes not be detected
* Fix broken timestamp processing.

v1.4.1
* fix main entry bug for cli

v1.4.0
* let the archive date override the newness of its contained files.
* let the cli be run programatically with passed in args
* code no longer relies on cwd for finding its way
* -d --directory argument goes away
* nosetests now run the old inadequate cli tests
* big code cleanup
* don't redetect new image format type

v1.3.3
* Print found picopt timestamps
* Lots of linting
* Fix jpeg_multithread flag
* moved tests out of picopt module

v1.3.2
* Keep __version__ in one place in picopt/__init__.py

v1.3.1
* Remove dev dependancies from installed requirements.

v1.3
* break up monolithic picopt into modules. No functional change.

v1.2
* picopt learned the -j option for specifying number of subprocesses (thanks @DarwinAwardWinner)

v1.1.3
* fixed rare crash on sequential gif detection

v1.1.2
* detect PNM images properly for conversion with optipng

v1.1.1
* fix verifying gif crash (thanks @DarwinAwardWinner)

v1.1.0
* mozjpeg support (thanks to @crass00)

v1.0.6
* Fix comic archive switch which was disabled somehow

v1.0.5
* Fix timestamp writing to really happen once workers have finished
* Fix size saved if size in is zero

v1.0.3
* Fix -v to actually be more verbose than default
* Fix from Dennis Schwertel to jpegtran runner

v1.0.2
* Fix -Y to actually disable not enable type conversion

v1.0.1
* Fix typos in --help

v1.0.0
* Packaging for PyPI
* Internal changes to make picopt more modular and library friendly
* CHANGED COMMAND LINE ARGUMENT LETTERS! WATCH OUT!
* Added verbosity setting
* Truncated relative and in-archive path names for readibiliy
* Nag about animated gifs less


v0.12.0.1
* Fix error on no directories

v0.12.0
* Added multithreaded jpegrescan operation when picopt isn't using up all the cores at the suggestion of Alex Roe.
* Added destroy metatdata option at the suggestion of Alex Roe.

v0.11.4
* Added to ArchLinux by Alex Roe.
