Re: [PATCH] Fix emms-tag-editor-rename-track to support slash in newname

> It would be much easier to simply replace the forward slash in the
> artist/album name with the Unicode visual equivalent of a forward slash
> such as DIVISION SLASH U+2215 or FRACTION SLASH U+2044. This way we
> preserve this feature for people who actually want Emms to help them
> create a directory structure for their music collection.

I select '_' as a replacement of '/', because:

1. It's a ascii char which should have a good display in all platform (I guess?).
2. It's just a connect character, I mean it has not obvious meaning, not like '&' can mean 'and', '+' can mean plus, etc.

I found some alternative char of '/' such as U+2215 you mentioned, but I'm not good at font. If those unicode charactors can behave correctly with most fonts, I think they are good replace for '/' too.

Maybe we can add a new var called 'emms-tag-editor-rename-replace-list'? which has a format like
(('/' '_') ('\' some_unicode_char) (':' some_unicode_char))
It can handle any chars such as '/', '\', '<', '>' (windows has many forbidden chars in filename). So emms can have a good work on windows.