This commit adds support for the libvirt live_migration_progress_timeout
and live_migration_completion_timeout parameters. These parameters are
useful for configuring timeouts for live_migration in cases where the
network is slower (e.g. 1GbE) or where the RAM usage is large. In both
these cases, timeouts can occur while live migrating using the default
libvirt values in nova.
Change-Id: Id728b3aa184d4218fcecea4e716e3b644668af85
a8e3d482be