Launcher: Use Desktop.getDesktop().browse().

The BrowserLauncher class seems to be really outdated (from 2001) and it doesn't even launch the browser on my Mac OS X.

Since Java 1.6, there is java.awt.Desktop, which can open a browser as well, so let's use that one.

Launcher: Use Java 6 SwingWorker instead of "Version 3 SwingWorker".

There was an old backport of SwingWorker for JDK < 6 from 2003, which was known as "SwingWorker Version 3".
Openfire does not need such old backports anymore.

Java 7: Collapse identical catch blocks.

Java 7: Replace explicit type with diamond operator <>

OF-343 Add @Override annotations

There were still ~1500 missing annotations! This time fixed with IntelliJ ;-)

Prevent NoClassDefFoundError during Openfire start.

Restore tray icon click functionality after moving to AWT tray.

Fix JDK 8 ambiguity with wildcard imports.

Clean plugins directory when calling Ant "plugins" target.

OF-967 add option to use Name as nickname for muc bookmark

Don't know why, but it fixes the issue described here:
https://community.igniterealtime.org/thread/55868

org.apache.jasper.JasperException: XML parsing error on file /WEB-INF/web.xml

java.util.* and org.jivesoftware.util.* both import Base64 class. The compiler cannot know which one to use.

Error message is:
both class java.util.Base64 in java.util and class org.jivesoftware.util.Base64 in org.jivesoftware.util match

REST API plugin: make group affiliations per room visible

This patch shows which groups have one of the affiliations
admin|member|owner|outcast.
In case the new query parameter expandGroups is set to true, the group
member's jids are added to the explicit jids.

These are actually not required by Java compiler and therefore have been removed with dfb69a76, but qdox needs them.

f81c28be replaced org.jivesoftware.util.Log with org.slf4j.Logger.
This commit partially reverts this.

Apparently the build process produces an additional startup.jar, which contains the ServerStarter class. However, it doesn't add slf4j-api.jar to the classpath or manifest.
Because Openfire's classpath, lib folder and build structure is pretty confusing (e.g. slf4j-api.jar gets merged into a new openfire.jar, there's an extra JiveClassLoader, etc...), it's hard to solve this in a reasonable way at the moment.

OF-938: Apply packet namespace via string insert

This patch fixes a problem introduced by an earlier patch whereby a
change to the Packet namespace inadvertently cascaded to child XML
elements.

OF-966 <failure> tag not closed for TLS Negotitation Failure

Use StandardCharsets.UTF_8 with Reader/Writer classes.

This is a followup for fcf665a9.

Use real Java enums for presence subscription states.

The homemade IntEnum and Enum classes feel totally weird and confusing, when having java.lang.Enum around.

This commit removes these classes.

The static constants in the RosterItem class now feel superfluous, but are kept in there, because they are referenced by a lot of other classes and JSP pages.

Use Collections.singleton() where ArrayList has only one element.

Fix PluginClassLoader load resource path issue  

Use try-with-resources statement to properly close resources.

Replace deprecated org.jivesoftware.util.Log with org.slf4j.Logger