8145301: Improve and unify the printout format for the g1HRPrinter.
Reviewed-by: brutisso, tschatzl

8145092: Use Unified Logging for the GC logging
Summary: JEP-271. VM changes contributed by brutisso, test changes contributed by david.
Reviewed-by: sjohanss, david, brutisso
Contributed-by: bengt.rutisson@oracle.com, david.lindholm@oralce.com

8139867: Change how startsHumongous and continuesHumongous regions work in G1.
Reviewed-by: tschatzl, tbenson

8042668: GC Support for shared heap ranges in CDS
Summary: Added "Archive Region" support to the G1 GC
Reviewed-by: tschatzl, brutisso
Contributed-by: tom.benson@oracle.com

8079792: GC directory structure cleanup
Reviewed-by: brutisso, stefank, david