8173335: Improve logging for j.l.ref.reference processing
Summary: Add logs for each phases of references and stats for each worker threads
Reviewed-by: tschatzl, shade

8155224: Bring back version control history to g1Policy.hpp and g1DefaultPolicy.*
Reviewed-by: pliden, mgerdin, sjohanss

8154753: Turn G1Policy into an interface
Reviewed-by: sjohanss, mgerdin

8154154: Separate G1 specific policy code from the CollectorPolicy class hierarchy
Summary: Move G1 runtime policy code to new class G1Policy which is unrelated to CollectorPolicy
Reviewed-by: kbarrett, ehelin

8146399: Refactor the BlockOffsetTable classes.
Reviewed-by: mgerdin, jwilhelm, tschatzl

8135152: Create a G1ParScanThreadStateSet class for managing G1 GC per thread states
Reviewed-by: tschatzl, ehelin

8040162: Avoid reallocating PLABs between GC phases in G1
Summary: Allocate G1ParScanThreadState at the start of GC and only deallocate at the end of GC. This automatically keeps the current PLAB intact without flushing it (and loosing lots of memory) for every reallocation.
Reviewed-by: david, mgerdin

8073052: Rename and clean up the allocation manager hierarchy in g1Allocator.?pp
Summary: Fix naming of G1ParGCAllocator, decrease dependencies between G1CollectedHeap, G1Allocator and G1AllocRegion, additional documentation.
Reviewed-by: mgerdin, jmasa, kbarrett

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