RFR: [9] Bulk backport to sh/jdk9

[Aleksey Shipilev]

http://cr.openjdk.java.net/~shade/shenandoah/backports/jdk9-20171114/webrev.01/

Fixes:

rev 13737 : [backport] Disallow pinned_cset region moves and allocations during Full GC
rev 13738 : [backport] Verifier crashes when reporting multiple forwardings
rev 13739 : [backport] Report all GC status flags in hs_err

Testing: hotspot_gc_shenandoah {fastdebug|release}

Thanks,
-Aleksey