Implements a small language parser to define the emulator events. The
event specification is parsed at emulation (when the emulator runs).
The ovnidump output now prints the events with the arguments formatted
as given in the event description.
It also introduces some consistency checks over the event MCVs, which
must begin with the model identifier and cannot be duplicated.
Until now, emulation models were always being registered via probe(),
which causes the emulator to initialize all the channels. To reduce the
overhead, the channels were not connected or registered in the bay
until the first event of that model was received. This delayed connect
was causing issues in muxes where the newly connected model required
refreshing the touched channels. Which in turn was causing unexpected
PRV events.
By determining which models we need to enable, we can remove the delayed
connect mechanism and just enable those models at initialization time,
and connect the channels.
Prevents enabling more channels than required until we observe an event
of that model. Ideally we should implement this logic in the probe hook
when the models can report if they are being used in the metadata.
