make: Install stanza watcher library (thanks Menel)

mod_admin_shell: Add watch:stanzas() command

mod_debug_stanzas/watcher: New module library to dynamically 'watch' for stanzas

mod_s2s: Store real stanzas in session.sendq, rather than strings This is the "right" thing to do. Strings were more memory-efficient, but e.g. bypassed stanza filters at reconnection time. Also not being stanzas prevents us from potential future work, such as merging sendq with mod_smacks. Regarding performance: we should counter the probable negative effect of this change with other positive changes that are desired anyway - e.g. a limit on the size of the sendq, improved in-memory representation of stanzas, s2s backoff (e.g. if a remote server is persistently unreachable, cache this failure for a while and don't just keep forever queuing stanzas for it).

Merge 0.12->trunk

mod_storage_xep0227: Fix mapping of nodes without explicit configuration Turns out this table was wrong, it's missing some fields which are required and it's 'name', not 'node'. Setting it to the boolean true invokes compatibility behavior in mod_pep which results in the correct default structure.

Merge 0.12->trunk

mod_storage_xep0227: Fix conversion of SCRAM into internal format (fix #1741) Looks like this function was a copy of hex_to_base64 without modifying it to do its inverse.

mod_storage_xep0227: Support basic listing of PEP nodes in absence of pubsub#admin data Allows migrating PEP nodes with default settings

mod_storage_xep0227: Improve logging What were we looking at?