Provides a CLI and API argument to force live migration, which triggers
a new VM state "migrate-live". The node daemon VMInstance during migrate
will read this flag from the state and, if enforced, will not trigger a
shutdown migration.
Closes#95
Implements wait support for VM restart, shutdown, move, migrate, and
unmigrate commands, similar to node flush/node unflush.
Includes some additional refactoring of the move command to make its
operation identical to migrate, only without recording the previous
node.
References #72