7115199: Add event tracing hooks and Java Flight Recorder infrastructure

Added a nop tracing infrastructure, JFR makefile changes and other infrastructure used only by JFR.

Reviewed-by: acorn, sspitsyn

hotspot/src/share/vm/runtime/os.cpp

@@ -1101,6 +1101,7 @@ bool os::set_boot_path(char fileSep, char pathSep) {
         "%/lib/jsse.jar:"
         "%/lib/jce.jar:"
         "%/lib/charsets.jar:"
+        "%/lib/jfr.jar:"
 #ifdef __APPLE__
         "%/lib/JObjC.jar:"
 #endif