MSO: enable waveform dump for several channels.
Add trivial loop over channels data to be dumped to disk. Several channels can now be passed to the CLI.
Add config for new runs (read SiPM + 2 PMTs, longer time window).
- Sampling rate now hardcoded to 5 GSa/s.
- sinc interpolation deactivated (increased output size by a sizeable amount: x2 to x8).
Add a couple checks on the settings.