hg: jdk10/sandbox: Merge

[ashipile at redhat.com]

Changeset: a64954ea255d
Author:    shade
Date:      2017-04-19 21:33 +0200
URL:       http://hg.openjdk.java.net/jdk10/sandbox/rev/a64954ea255d

Merge

- README-builds.html
- README-builds.md
- common/bin/shell-tracer.sh
- common/bin/update-build-readme.sh