when we reset a notch we need to init the stored values to the current
value, rather than assuming that zero is the right value
this matters when switching IMUs in flight when we are only running
notch filters on the active gyro
This delegates updates to a bank of NotchFilters located at an rpm frequency and harmonics. Center frequency can be updated dynamically. Notch parameters are configurable, including the number of harmonics to filter on. Updates to the filter parameters are optimized across the notch bank. Convert notch bandwidth and frequency to floats.
allow all filter harmonics to be controlled.
add destructor to harmonic notch.
don't allocate sub-filters for harmonic notch if no harmonics set.
