inconsistent latencies

[lennart]

the current implementation relies on latency of a Shape to be set high enough to avoid late messages that may produce unwanted drops off note or cc events.

the latency is therefore highly dependent on the host machine tidal-midi is running on.

it may be that the current 0.8/0.9-dev implementation is counterintuitive and we might need to express this avoid lateness delay with another shape parameter. (or even better, get rid of the problem altogether)

each synth in tidal-midi currently has its own latency setting, that may or may not feasible, I don't know whether these values are chosen to reflect the hardware latency, or something else.

for a proper 0.9 release we should at least consolidate these settings and document the configuration options.