[WIP] Extract sync event timestamps from SpikeGLX streams

[guptadivyansh]

Slowly working towards https://github.com/SpikeInterface/spikeinterface/issues/2234

Trying to reuse the nidq digital channel event processing for handling sync edges. Will then align edges and change sampling rate/time vector as necessary

Also, I'm not sure if any of the current test files have simultaneously recorded sync signals in both imec and nidq streams.