Changes

<s>[https://bugzilla.mozilla.org/show_bug.cgi?id=254519 Bug 254519]</s>: Incorrect RFC 2047 encoding and decoding. This is one of the most-duped bugs in the mail domain. When replying to a message with an RFC2047-compliant header that happens to contain a comma in the name --e.g. <u><tt>Müller, Wolfgang</tt></u> -- the comma is interpreted as an address separator, and the reply goes to two different recipients, <u><tt>Müller</tt></u> and <u><tt>Wolfgang</tt></u> (and the actual mail address is only supplied to the second). A MIME-encoded name field is supposed to be treated as an atom; special characters contained within are to be treated literally.