[Standards] New ProtoXEP: Pubsub Node Bookmark

Hi, I'm submitting a new XEP named Pubsub Node Bookmark after the work we did with nicoco on the XEP-0503: Spaces. This XEP is quite simple and defines a new <pubsub-node/> element that act as a bookmark that point to a Pubsub Node. The goal is to have something very similar to the <conference/> node defined in XEP-0402: PEP Native Bookmarks, a <pubsub-node/> is even having an <extensions/> item that is compatible with the ones of XEP-402, allowing Pubsub Node Bookmarks to be pinned (https://xmpp.org/extensions/xep-0402.html) or having custom notifications settings (https://xmpp.org/extensions/xep-0492.html). As you see in the example bellow the id is defined the same way as the ids in XEP-0402 but this time by using a Pubsub URI. Here is an example: <itemid='bookmarks.library.org?;node=books'><pubsub-nodexmlns="urn:xmpp:pubsub-node_bookmark:0"jid="bookmarks.library.org"node="movies"><extensions><pinnedxmlns='urn:xmpp:bookmarks-pinning:0'/></extensions></pubsub-node></item> Why this XEP ? A Space is defined as a list of items in a Pubsub Node, those items can be MUCs but also Pubsub Nodes (for example if you want to have a Blog or Newsletter in your Space). Movim is using something a bit similar in an old XEP I defined in 2013: https://xmpp.org/extensions/xep-0330.html, if Pubsub Node Bookmark is published, I'll update XEP-0330 to be based on that one. You can find a HTML version there: https://movim.eu/xeps/pubsub-node-bookmark.html I'd be happy to get feedbacks to see how things can be improved :) Regards, edhelas