small typo in Changelog.md
another small typo.
Fixing issue around removing listeners

When removing listeners, the comparison of the callbacks can fail. This was best seen when trying to remove cue points.
Fixed leaked for loop i

Ref issue #21
Merge pull request #19 from gustavpursche/patch-1

Small typos in Changelog.md
Merge pull request #21 from jason-brodie-codebaby/master

Fixing issue around removing listeners
Merge pull request #23 from jason-brodie-codebaby/patch-1

Fixed leaked for loop i