[Feature] Add more metadata fields

[dannyglover]

Here are some more fields that would be great to add support for:

tag.trackArtist, -- added via https://github.com/erikas-taroza/audiotags/pull/10
tag.albumArtist -- added via https://github.com/erikas-taroza/audiotags/pull/10
tag.originalReleaseDate,
tag.trackNumber -- already supported
tag.trackTotal -- already supported
tag.discNumber -- added via https://github.com/erikas-taroza/audiotags/pull/10
tag.discTotal -- added via https://github.com/erikas-taroza/audiotags/pull/10

All of these fields are available in lofty.
I know you already have the tag.artist field, but having both track artist and album artist fields would be great. I believe you recently added tag.trackNumber, from my previous feature request, so feel free to ignore that.

Thanks again Erikas!

PS: I've been working on setting up my dev environment, so I may chip in to adding support for some of these fields, as it would be a good first assignment in familiarizing myself with your codebase.

Cheers :)

[erikas-taroza]

PS: I've been working on setting up my dev environment, so I may chip in to adding support for some of these fields, as it would be a good first assignment in familiarizing myself with your codebase.

These changes are pretty simple so feel free to PR. For recordingDate and originalReleaseDate, you will have to use chrono to handle dates in Rust.

[dannyglover]

Edit: WIP PR for implementing the requested fields: #10

Review at your leisure, as I'm not finished implementing everything yet.