Storing offline messages without body content

Tigase can now store offline messages without <body/> content.

See XEP-0334 for protocol details.

This can include message receipts, and messages with specific do-not-store tags.

Support has been added to set a list of paths and xmlns to trigger and place storage of offline messages using the following settings in init.properties:

sess-man/plugins-conf/amp/msg-store-offline-paths[s]=/message/received[urn:xmpp:receipts],/message/store-offline

This example results in two settings:

/message/received[urn:xmpp:receipts]

Results in storage of messages with a recieved subelement and with the xlmns set to urn:xmpp:receipts

/message/store-offline

Results in storing messages with a store-offline subelement without checking xmlns.