[bug] \Z matches where it shouldn't (Issue #14)

see: http://bugs.ruby-lang.org/issues/8001
[dist] update testpy.py

Add tests for the Issue #14.
additional fix for Issue #14
Merge branch 'topic/fix-Z-matching'
update HISTORY and copyright
Merge branch 'master' into tmp/ruby-2.0.x

Conflicts:
	regexec.c