Implement optimized compression for Java 11+

Using the fact that the Java Deflater/Inflater API now supports
ByteBuffers as of Java 11, we can provide performance benefits equivalent
to the Velocity 1.0.x native compression on servers running Java 11+ on
non-macOS and non-Linux platforms (such as Windows).

proxy/src/main/java/com/velocitypowered/proxy/util/concurrent/VelocityNettyThreadFactory.java

@@ -17,7 +17,7 @@ public class VelocityNettyThreadFactory implements ThreadFactory {
 
   @Override
   public Thread newThread(Runnable r) {
-    String name = String.format(nameFormat, threadNumber.incrementAndGet());
+    String name = String.format(nameFormat, threadNumber.getAndIncrement());
     return new FastThreadLocalThread(r, name);
   }
 }