Fixed library version.
Fixed whitespace parsing before word.
Fixed parsing header field value on next line.
Also check for RFC-2047 end sequence.
Checks for a charset in all words of a parameter in a parameterizedHeader.

Fixes filename encoding when the quoted-printable starts halfway, but
if multiple charsets are used (unlikely) it may still fail (thanks to
Zarafa).
Let whitespace break the value of a parameterized header field, not just a ';' (thanks to Zarafa).