8179268: Factor out AdaptiveSizePolicy from top-level interfaces CollectorPolicy and CollectedHeap
Reviewed-by: pliden, sjohanss

6858051: Create GC worker threads dynamically
Reviewed-by: tschatzl, drwhite

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

7012980: PSOldGen is increased if there is no space in Metaspace
Reviewed-by: tschatzl, tbenson

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