backend, pgsql storage: better items/notification handling, various fixes: - replaced const.VAL_AMODEL_ROSTER by const.VAL_AMODEL_PUBLISHER_ROSTER to follow change in pgsql schema - implemented whitelist access model - fixed bad access check during items retrieval (access was checked on recipient instead of requestor/sender) - getItemsData and notification filtering now use inline callbacks: this make these complexe workflows far mor easy to read, and clarity is imperative in these security critical sections. - publisher-roster access model now need to have only one owner, else it will fail. The idea is to use this model only when owner=publisher, else there is ambiguity on the roster to use to check access - replaced getNodeOwner by node.getOwners, as a node can have several owners - notifications filtering has been fixed in a similar way - psql: simplified withPEP method, pep_table argument is actually not needed - removed error.NotInRoster: error.Forbidden is used instead - notifications now notify all the owners, not only the first one

--- a/sat_pubsub/const.py	Sun Mar 26 20:33:18 2017 +0200
+++ b/sat_pubsub/const.py	Sun Mar 26 20:52:32 2017 +0200
@@ -63,9 +63,12 @@
 OPT_SEND_LAST_PUBLISHED_ITEM = "pubsub#send_last_published_item"
 OPT_PUBLISH_MODEL = 'pubsub#publish_model'
 VAL_AMODEL_OPEN = 'open'
-VAL_AMODEL_ROSTER = 'roster'
-VAL_AMODEL_JID = 'jid'
+VAL_AMODEL_PUBLISHER_ROSTER = 'publisher-roster'
+VAL_AMODEL_WHITELIST = 'whitelist'
+VAL_AMODEL_PUBLISH_ONLY = 'publish-only'
+VAL_AMODEL_SELF_PUBLISHER = 'self-publisher'
 VAL_AMODEL_DEFAULT = VAL_AMODEL_OPEN
+VAL_AMODEL_ALL = (VAL_AMODEL_OPEN, VAL_AMODEL_PUBLISHER_ROSTER, VAL_AMODEL_WHITELIST, VAL_AMODEL_PUBLISH_ONLY, VAL_AMODEL_SELF_PUBLISHER)
 VAL_PMODEL_PUBLISHERS = 'publishers'
 VAL_PMODEL_SUBSCRIBERS = 'subscribers'
 VAL_PMODEL_OPEN = 'open'