Add parameters for sensing path ADC delay

This MR adds parameters adc_delay_cycles and adc_clock to the [sensing] section in order to permit modeling the ADC on the sensing path having some digital delay.

Note that adc_clock is now a required parameter; there is no fallback.

On the other hand, adc_delay_cycles is an optional parameter. If nothing is given then it is assumed to be 0 clock cycles delay

Closes #192 (closed)