Ffmpeg-normalize

* Add version info and test case for dry run.

* New feature detection, add documentation, contributors guide etc.

* WIP: v1.0 rewrite.

* Use shutil.move instead of os.rename.

* Allow setting threshold to 0.

* Bump version.

* Update HISTORY.md.

* Merge pull request 37 from Mathijsz/fix-which-path-expansion.

expand tilde and environment variables, fixes 36

* Expand tilde and environment variables, fixes 36.

* Update HISTORY.md.

* Update README w.r.t. loudnorm filter.

* Update README and indentation.

* Bump version.

* Fix handling of extra options with spaces.

* Include test script.

* Logging and other improvements.

* Add test files.

* Autopep8 that thing.

* Logger improvements.

* Add example for overwriting.

* Allow overwriting input file, fixes 22.

* Version bump.

* Better handle cmd arguments.

* Update README.md.

add another example