Support Content-Transfer-Encoding or more MimeHeaders

[schmitch]

Hello, currently it would be great if we would have more options in specifing Mime Data.

I think the only way to handle that as good as possible would be a more loose mime field which would just append the necessary Bytes.
Like a List[(String, String)] or something which will be appended without validation

[ggrossetie]

Could you provide a use case for this ?

[schmitch]

Mostly for Content-Transfer-Encoding. Currently It's not possible to specify base64 as a content-transfer-encoding, also I'm not sure if there are any more useful headers which couldn't be specified yet, so maybe a more "loose" would help here.

As I remember there way a MD5 Header and I think a alternative content header.