Reviewed-by: coleenp, eosterlund, mchung, ahgross, rhalade

8156137: SIGSEGV in ReceiverTypeData::clean_weak_klass_links
8057570: RedefineClasses() tests fail assert(((Metadata*)obj)->is_valid()) failed: obj is valid
Reviewed-by: coleenp

Reviewed-by: dholmes, kevinw

Reviewed-by: dholmes

Summary: Adding VM.dynlibs as a dcmd to dump all loaded dynamic libraries.
Reviewed-by: fparain, mgronlun

Summary: The information about loaded dynamic libraries printed in hs_err_pid files or by running the jcmd VM.dynlib is partly incorrect. The address printed in front of the library file name is wrong.
Reviewed-by: sla, gziemski, gtriantafill
Contributed-by: fredrik.arvidsson@oracle.com

Summary: Implement Diagnostic Commands for heap and finalizerinfo
Reviewed-by: mchung

Summary: modified jtreg tags and package import to work with JDK 8
Reviewed-by: vlivanov, dholmes

Reviewed-by: stuefe, stefank