Commit Briefs
fix gcc 4.8 warnings
LGTM=rsc R=rsc https://codereview.appspot.com/33240044
venti: fix format on ulong
R=rsc CC=plan9port.codebot http://codereview.appspot.com/5328046
Fix a handful of small one-time memory leaks in vbackup,
and one per-package memory leak (in writethread).