[Bug 1087700] lost signals when sending lots of signals using --sig-proxy to docker

[Red Hat Bugzilla]

https://bugzilla.redhat.com/show_bug.cgi?id=1087700

--- Comment #6 from Matthew Heon  ---
A fix for this has made its way upstream
(https://github.com/dotcloud/docker/pull/6508#issuecomment-48211901), and
should be included in the next upstream release of Docker.