[libvirt] [PATCH 0/4] Support for sending signals to guest processes

One of the things people want to be able todo with LXC is to send arbitrary signals to processes inside the container. This series introduces a virDomainSendProcessSignal API for that purpose. The LXC driver impl is limited to sending signals to the "init" pid (ie pid == 1), but in the future we'll extend this to arbitrary container PIDs (via /proc/$PID/ns/pid + setns()). If the QEMU guest agent had a suitable command we could support this for QEMU too.