testing/soundfont-vintage-dreams-waves: new aport

This will add a soundfont that is to be used with fluidsynth. Since there are no other packages of this kind packaged already for alpine; I used soundfont-* namespace for package name, and /usr/share/soundfonts/ base path for the font files.

The source does not contain a license file. It has been declared free to use on their website though.

The soundfont is also in fluidsynth sources. So redistributing it should not be an issue.

I'm open to suggestions/questions.