Add support for adding meta-data and tags to files

[stevestencil]

Is your feature request related to a problem? Please describe.
Currently when saving files, the only thing you can set is the data itself and the file name. The ability to add additional meta-data and tags (specifically with S3) would be a great feature add

Describe the solution you'd like
Being able to pass in a "metaData" and/or "tags" key to the options object when saving a file. These two values would be sent to S3 along with the file data. Also, if support for beforeSaveFile and afterSaveFile are implemented (#6340), these metaData and tag values could be set there too. This would make it possible for things like deleting all files a user created once their account is deleted, etc.

Describe alternatives you've considered
None

Additional context
I have no problem adding this along with #6340 if the community will accept the changes.

[davimacedo]

I think it is a good idea and can be worked together with #6340

@dplewis @acinader thoughts?