OF-974: Migrate cache content

Add Legacy Jive build code for eventual removal

When switch to/from clustered deployment, ensure that critical cached
items such as components and remote servers are not inadvertently
dropped from the cache.

By replacing Jetty 6.x era libraries with 9.x-based variants, JSP support
will be brought back up-to-date. Additionally, Openfire will no longer
have a mix of dependencies from various versions of Jetty. This commit
contains a number of changes that go hand-in-hand:
- Replaces JAR files
- Applies uniformity to the buildscript where JSPC is executed
- Replaces JSTL 1.0 taglibs with later versions
- Adds a simple logger to the build process (to stop it from complaining)

Various improvements in Version class

byte[].equals() should probably be Arrays.equals()

Adding PropertyListener support to AuditManagerImpl

StringUtils: Simplify verbose/duplicate and obsolete code constructs

Replace deprecated JiveConstants.XMPP_DELAY_DATETIME_FORMAT usage

OF-868 update roster cache on userModified

Tests should retrieve resources from the classpath rather than files.

Delete ChannelInputStream.java.

Cleanup connection logging, etc.

Update protocol support documentation.

Modernize XMLProperties with Java NIO.2 File API

Delete URLUTF8Encoder.java in favor of java.net.URLEncoder.

Revert PR#300 (restore PluginClassLoader)

per discussion with core team

Also remove dependency for sun.security.provider.* package

This is highlighted as "probably a bug" in my IDE.

E.g. `new byte[]{1}.equals(new byte[]{1})` is always false.
But `Arrays.equals(new byte[]{1}, new byte[]{1});` is true.

- The 4 replace methods were nearly identical.
- Deprecate String utility, which has a simple one-liner equivalent in the JDK
- Use DatatypeConverter for byte[] to hex. It's less code and even 2-3 times faster than the previous method.

OF-881: Simplify connection close semantics

- Use AtomicReference instead of synchronized block
- Extend java.io.Closeable; document contract
- Consolidate close/state transition logic

URLUTF8Encoder is obsolete due to `java.net.URLEncoder.encode(str, "UTF-8")`

This package-private class is a) unused and b) redundant due to `java.nio.channels.Channels.newInputStream(ReadableByteChannel)`

ofmeet plugin version 0.2.3

Simplified build, removed classes folder in WEB-INF
Changed default value for voip gateway to false
Removed some redundant and duplicate jar file in jitsivideobridge lib
Removed tinder.jar and whack.jar which caused ComponentManagerFactory.getComponentManager() to fail with OF 3.11

Avoid recursion and synchronization issues

Update REST API Plugin to 1.1.7

Added: Provide the possibility to use a Custom Auth Filter
Fixed: Preflight request will be not blocked by Authentication
Added: Group names in ChatRoom Entity

with XMPPDateTimeFormat

- Make it final and immutable.
- Use pattern-based parsing, which allows to also parse the ReleaseStatus and the statusVersion.
- Implement toString() method.
- Implement equals() and hashCode(), which is a strong recommendation when implementing Comparable: From the JavaDoc: "It is strongly recommended that (x.compareTo(y)==0) == (x.equals(y))", which was not the case.
- Allow CharSequence
- Simplify getVersionString() method (less duplicate code).
- Improve compareTo() method by properly comparing more than 2 digits and also comparing ReleaseStatus and statusVersion

- Update old XMPP RFCs to the new one (e.g. 6120)
- Remove the obsolete reference to XEP-0073 and replace it with XEP-0302
- Get rid of the basic/intermediate terms as they are no longer in use in XEP-0302. Use Core and Advanced instead.
- Add XEP-0160, XEP-0198, XEP-0202, XEP-0280
- Correct "Entity Time" to "Legacy Entity Time"
- Correct "Jabber Date and Time Profiles" to "XMPP Date and Time Profiles"

Revert "	Fix PluginClassloader not implement getResources Method"