Google is now requiring an API key in order to access YouTube Data
web services.

To obtain a key:

1. Create a new project at https://console.developers.google.com/

2. Select newly created project and go to Enable API,
   go to APIs & auth / APIs, select the Youtube Data API
   and click Enable.

3. Go to Credentials, click Create Credentials and choose API key.

4. If you are going to build minitube from ports, set
   MINITUBE_GOOGLE_API_KEY=your_key in make.conf. If you use package
   set GOOGLE_API_KEY environment variable to your key.

Make sure you also have a phonon4 backend installed at runtime:
multimedia/qt5-phonon4-gstreamer
-or-
multimedia/qt5-phonon4-vlc