add missing rut-nine-slice.c/h files
frontend: avoid redundant lookup in unregister_id_cb
frontend: use libtool to run sim for debug builds

This helps ensure that the simulator is using the in-tree librut library
frontend: remove unused object variable
frontend: bail from _queue_set_play_mode_enabled if redundant
renderer: fix several closure leaks
rig-rpc: don't unref pb_rpc_client/server owned by pb_rpc_peer
frontend: restart simulator if it crashes

When running as an editor we now detect when the simulator crashes and
switch back to edit mode before starting a new simulator.
Implement all remaining engine ops

This completes the implementation of all copy/map/apply functions for
all of the ops in rig-engine-op.c and also updates the journal to use
these ops.
don't pass -1 fd to rig_protobuf_c_dispatch_fd_closed
rpc: free message on closure free

This updates the rpc layer so that the unpacked message that gets passed
to us when servicing a request doesn't get freed immediately on return
from the service function, and instead gets freed when that requests
corresponding closure function is called, signalling that the request
has been handled.

This is necessary for rig-slave to be able to batch edit messages until
it is ready to send them to the simulator.