OF-1030 prevent entry of 'any' as date to cause exception

* AvatarPlugin: Add prior-to-openfire 4.2.0. restriction

* Merged avatarResizer plugin with Openfire core (prevents OF-1145 & OF-1193)

OF-1424: Use weakly consistent impl to prevent CME.

OF-1423 Honour configuration for message size

Allow code reuse from plugins

* WIP: XEP-0198 Stream Resumption

This patch implements a first cut of XEP-0198
Stream Resumption for TCP and WebSockets.

This appears to work on (very) basic testing, but
the code is very likely to run into problems with
existing code assuming that LocalSession.getConnection()
never returns null, and similar issues.

This is likely to generate unexpected (and
possibly unhandled) NPEs.

The basic premise to the design is that
StanzaHandlers (or similar) and Connections
from the new session are re-pointed to the old
session. The old session lives on in limbo with its
conn field set to null during detachment.

I strongly suspect that bits are missing from this,
but so far...

* Fix CR/LF

* WIP

* WIP

* Close detached 198 sessions after timeout

Also:
* Quick audit of LocalSession.getConnection
* Add in guard code for LocalSession.getConnection

* CRLF

* CRLF

OF-1416: Ensure that hazelcast cache entries expire correctly

* Update JustMarriedPlugin.java

* OF-1134 - Update copied users nickname on other users rosters

* OF-1134 - Update copied users nickname on other users rosters

Updated version and changelog

* OF-1422 Check all MUCRoles to see if this is rejoin

* Handle errors and other presence better in MUC

Also refuse nickname changes on shared nicknames,
since they don't currently work.

* Crazy wRong Line-ending Fix

Use a ServletRequestAuthenticator to authenticate SiteMinder users

OF-1335 Part Two: Strip namespaces differently

Disable External Entities in plugin.xml

Openfire already uses xmpp.parser.buffer.size as
the maximum stanza size in NIO client sessions.

This change ensures that this is also used when
configuring Websocket sessions.

This checks to see if any occupant exists with
the same full jid, and if so treats this as a
clientOnlyJoin (ie, rejoin).

This commit grew a little larger than anticipated - my apologies for the reviewer. The original intend
for this was to allow changes in the java Keystore to be applied, without requiring a restart of Openfire.
This is what allows outside processes to update the Keystores - think Let's Encrypt - but could also be
useful for other purposes.

In the process of writing this code, I've found that a restart of the Connection Acceptor would still cause
all existing connections to be terminated. This is why a 'reload configuration' method was added.

I've found that the old Certificate Event Listener methods were unuseful. They were pretty detailled, but
all implementations used them in the same way: "reload everything". I've replaced those with one
'something changed' event. Also, the event listeners are no longer triggered in various places in the code.
Instead, the event listeners will now be triggered by the filesystem-based change of the keystore - the same
event that's used to reload configuration when Let's Encrypt updates pop up.

I've removed various bits of lengthy, unused code in the old CertificateManager (primarily code that
interacts directly with KeyStores, as that caused timing issues during the reload).

One functional change (that was marked as 'unsure why we do this' in code) is that after this commit, the
content of the identity store is no longer merged with the content of the trust store, while determining if
a particular end-entity certificate is to be trusted.

* OF-1418: Be less noisy with user not found.

* Fix line endings!

* Also do something similar with GroupNotFoundException

OF-1335: Don't strip namespaces everywhere.

Openfire prevents the need to re-scope XML (as described in RFC 6120 section 4.8.3) by
pre-emptively remove certain namespaces (such as 'jabber:client' and 'jabber:server').
It should not, however, remove these namespaces everywhere. This commit prevents such
removal in places other than the first and second level elements (typically: stream
and stanza elements).

I replaced the info for the old Community with the info for the new Discourse one and added a link to the Community under Resources.

OF-1412 Add automated setup support on first run