mod_invites_page: Remove preauth URI button This button is incompatible with the majority of XMPP clients around, yet based on feedback from users, many are drawn to click it when they have any XMPP client installed already. In the case where the user already has software installed, we would prefer them to select it from the software list so they can follow the setup process suited to their specific client (we already track which software supports preauth URIs). If their client is not listed, they can still use the manual registration link instead.

mod_conversejs: Add comments about default settings

mod_conversejs/README: Complete list of auto-injected settings

mod_conversejs/README: Add text about preventing auto-load of mod_bosh/ws

mod_conversejs: Tweak wording Unqualified "It" read weirdly

mod_log_ringbuffer: New module to send logs to an in-memory ringbuffer

mod_s2s_keepalive: Fix name of timestamp function

mod_s2s_keepalive: Use timestamp as iq @id RFC 6120 implies that the id attribute must be unique within a stream. This should fix problems with remote servers that enforce uniqueness and don't answer duplicated ids. If it doesn't do that, then at least you can get a guesstimate at round-trip time from the difference between the result iq stanza and the timestamp it was logged without having to go look for when it was sent, or needing to keep state.

mod_welcome_page/html: Containerize the Jumbotron! This makes the jumbotron not take up the whole screen, if the screen is large-ish.

mod_invites_page: Fix table in README (thanks Ge0rG)