[pmc] More WB optimizations

Signed-off-by: Reini Urban <rurban@cpanel.net>
[pmc] Fixed WB Bugs

Signed-off-by: Reini Urban <rurban@cpanel.net>
[pmc] destroy is not :write. mark as :no_wb

This fixes the parrot and nqp benchmarks numbers
[pmc] Optimize dynpmc WB and testlib/nci_pmc.in

mark non-writers as :no_wb
t/codingstd/copyright.t: allow year-year,year

copyrights are only defendable on actual changes. overly broad ranges
are not accurate. allow adding single years, or multiple ranges.
See eg. select.pmc: 2011,2014, or file.pmc: 2001-2011,2014,

Fixes GH #1074
bump VERSION to 6.5.0
Merge branch 'rurban/pmc2_orig3-gh1069'

Last part of Chirag's GSOC #1. Some bugfixes
and some more WB optimizations.