This commit introduces a new ContentDisposition class designed
to parse and generate Content-Disposition header value as defined
in RFC 2183. It supports the disposition type and the name,
filename (or filename* when encoded according to RFC 5987) and
size parameters.
This new class is usually used thanks to
HttpHeaders#getContentDisposition() and
HttpHeaders#setContentDisposition(ContentDisposition).
Issue: SPR-14408