v0.25.0

Signed-off-by: James Robert <me@jiaaro.com>

Merge pull request jiaaro#488 from GreyAlien502/v0.24.1

update changelog and version

run CI tests on python 3.7

bug fix release

Merge branch 'master' of https://github.com/jiaaro/pydub

increment version

Merge pull request jiaaro#205 from jiaaro/fix-193

fix jiaaro#193