removed dead & unused code, typos
Mail\Message::setHtmlBody() decodes %XX in URL
Mail\MimePart::encodeHeader() fixed counting of offset
Mail\MimePart::encodeHeader() - do not use base64 encoding for long headers [Closes nette/mail#4] partially
Mail\MimePart::getEncodedHeader() don't use base64 encoding where can be quoted string [Closes nette/mail#4]
removed set_magic_quotes_runtime()