as2-lib 4.1.1

Use only with ph-commons 9.1.4 or newer

• The existence of the header Disposition-Notification-Options without Disposition-Notification-To does not trigger MDN sending (see #42)
• Fixed overwriting of existing Content-Transfer-Encoding when receiving messages.
• Partnership attribute blockerrormdn is now only evaluated for MDNs that are created based on errors
• MDNs now also use the partner attribute content_transfer_encoding and content_transfer_encoding_receive (see #43)

Dependencies required:

• ph-commons/ph-xml/ph-collection/ph-security/ph-datetime/ph-bc 9.1.4
• ph-mail/ph-http/ph-network 9.0.2
• BouncyCastle 1.60