Graphic EQ Effect

Thiss PR adds a 10 band static equalizer based on Biquad filters. The implementation of the Biquad filter is based on @daschuer's iireqs branch.
On one hand a 10 Band EQ is most common, on the other hand I really like to limit the parameter count to 8 to save space on small GUIs. What about hiding the 16k and 31 band at the effect rack and offer it only in the full view?