Merge 0.12->trunk

mod_admin_shell: Allow matching on host or bare JID in c2s:show Only supporting exact match on full JID isn't helpful if you want to list sessions per host or user. Backport of 430333198e4c Fixes #1857

mod_blocklist: Drop blocked messages without error, option to restore compliant behavior From XEP-0191: > For message stanzas, the server SHOULD return an error, which SHOULD > be <service-unavailable/>. Following this may leak to a blocked JID that they have been blocked, which seems contrary to the goal of pretending to be perpetually offline.

mod_pep: Implement 'roster' (group) access_model Allows e.g. restricting your vcard4 to only family or similar. Notes: This does not include roster groups in the configuration form, so the client will have to get them from the actual roster.

mod_announce: Suppress luacheck warnings

mod_announce: Add shell commands and APIs for sending to all/online/roles

prosodyctl shell: Fix invocation with 3+ command arguments The code correctly inserted the ',' when there was already a "%q" in the format string, but then the next argument would fail to match because it inserted ", %q" instead of "%q". The code now matches both, ensuring the generated code will not produce a syntax error with multiple arguments.

mod_blocklist: Fix fix signal for letting stanzas pass Returning nothing/nil lets stanzas pass, returning anything else blocks

mod_blocklist: Check JID of mediated MUC invite sender against blocklist This ensures that someone on your blocklist is unable to invite you to MUC rooms.

mod_saslauth: Log when tls-exporter is NOT supported, as well as when it is