libvirt security and bug fix update

1.1.1-29.0.1.el70.4 - Replace docs/et.png in tarball with blank image 1.1.1-29.el70.4 - qemu: blockcopy: Don't remove existing disk mirror info rhbz1149078 - qemu: copy: Accept 'format' parameter when copying to a non-existing img rhbz1149078 - qemu: reject rather than hang on blockcommit of acti...