Fixes

• Fixed bug where TranscriptsDisabled wasn't raised properly (thanks to @xenova!)
• Fixed Typo in the FormatterLoader, which was preventing the WebVTTFormatter from being loaded properly (thanks to @MAJA-Lin!)

Breaking

• Dropped support for python 2.7. While this module should currently still run on python 2.7, it has been removed from the travis builds, therefore, there is no assurance that future versions will run with python 2.7.