OF-1540 Rest API, delete room should send RoomRemovedEvent to cluster

* Adding GZIP functionality

Fixed: That created rooms were not propagated to other nodes OF-1535
Fixed: Missing documentation for "new" json mapping

* OF-546: Drop Apache Ant in favor of Apache Maven.

This commit removes support for Apache Ant, and replaces (some, not all)
references with references to Apache Maven.

* OF-546: Remove bundled libraries for plugins.

This removes all bundled binary libraries from plugins that can be build with Maven instead of Ant.

Motivation:
Give third-party developers more flexibility to build their plugins. Currently it's not possible to filter anything besides the plugin.xml.

Further improvements:
- Include lib folder in the assembly (for non-Maven artifacts)
- Update namespace "http://maven.apache.org/plugins/maven-assembly-plugin/assembly/1.1.2" -> "http://maven.apache.org/ASSEMBLY/2.0.0"

OF-1515: Migrate Private XML Storage to PEP

Openfire supports XEP-0049, Private XML Storage. However, Openfire can also be used for
XEP-0223: Persistent Storage of Private Data via PubSub. When a user previously used more
than one client, where each client would use a different XEP to store private data, the
private data that was stored by one client would not be shared with the other client. This
is undesirable, as such data typically includes data that benefits every client used by the
user.

In this commit, all data that is stored in the Private XML Storage database table will be
migrated to PEP. After a successful migration, the old database table is deleted.

Openfire continues to offer XEP-0049: Private XML Storage functionality. However, whenever
data is obtained or modified through methods defined in that XEP, the PEP data is modified.

OF-1511 OF-1513 OF-1514: Pubsub / PEP changes

OF-1519 add info about firewall

OF-1518: Ensure the summary is properly escaped

OF-1509: Add thread safety when incrementing counter.

* Release 2.3.0 of the Hazelcast plugin

* Correct the date

This updates the inVerse plugin to use the latest upstream release. As suggested by JC, it's author,
I've also disabled the 'viewMode' configuration option for now (this should be reenabled in future
releases).

OF-1345 Can't create/reset passwords when using HybridAuthProvider

OF-1421: Drop Java 7 support, require Java 8.

OF-1504: Caching the session will prevent carbons.

OF-1508: Prevent empty entity caps hash lookups.

* Updating the REST API Plugin to 1.3.0

Added: Security Audit endpoint to get the security logs
Added: More details by error
Improvement: Better JSON mapping (e.g. single element in an array bug)

* Adding missing libs for the ANT job

* Fixing the date for the plugin

2018 instead if 2017

OF-1507: Handle S2S stream errors.

OF-1191: Add BOSH mutual authentication config to admin console.

OF-1505: Prevent admin console stacktrace on TLS config page.

HZ-9: Ensure clustering works properly when enabled through the admin UI