New and changed information

Added implementation details of Java Flight Recorder (JFR).

Updated G1GC collector and Java SE features not implemented in NSJ 11 for new support information.

Native Memory Tracking is supported. For more information about this feature, see Oracle JDK 11 documentation.

Added enhancements to Emslogger.

Included perf.attach feature that enables a Java application to attach to another running Java application and collect performance data. See Perf.attach.

Added mmaphelper section.