Expose Tag's default encoding

[deanishe]

Perhaps I've missed something here. Adding my own TextFrames to Tags seems to be more complicated than it need be, as Tag doesn't export its default encoding.

The Tag.Set* convenience methods use TextFrame{Encoding: tag.defaultEncoding ...}.

Because Tag.defaultEncoding isn't exported, you need to re-implement Tag.setDefaultEncoding() to add your own TextFrame.

(I'm assuming I shouldn't just smush UTF-8 TextFrames into a Tag whose version is < 4.)

[n10v]

Done in 7e43476:

// DefaultEncoding returns default encoding of tag.
// Default encoding is used in methods (e.g. SetArtist, SetAlbum ...) for
// setting text frames without the explicit providing of encoding.
func (tag *Tag) DefaultEncoding() Encoding {
	return tag.defaultEncoding
}

// SetDefaultEncoding sets default encoding for tag.
// Default encoding is used in methods (e.g. SetArtist, SetAlbum ...) for
// setting text frames without explicit providing encoding.
func (tag *Tag) SetDefaultEncoding(encoding Encoding) {
	tag.defaultEncoding = encoding
}