Update buildah spec file to match new version
Update buildah spec file to match new version

Match the version 0.4 in the spec file and add the
comments that went into Fedora release

Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>

Closes: #269
Approved by: rhatdan

projectatomic/buildah,nalind/buildah,TomSweeneyRedHat/buildah,nalind/buildah-1,projectatomic/buildah,rhatdan/buildah,TomSweeneyRedHat/buildah,rhatdan/buildah,nalind/buildah,nalind/buildah-1,ipbabble/buildah,nalind/buildah-1,TomSweeneyRedHat/buildah,rhatdan/buildah,ipbabble/buildah,projectatomic/buildah