EQ Fixes for 1443

fixes for #1443
analyser now disabled when not in view.
band vu meters now disable when analyser is disabled.
display name changed to Equalizer.
set sample rate before frequency on LinkWitzRiley filters.
Grouped the setting of filterparameters into one function, and calc coefficents once if needed.
Made suitable functions inline.
in and out vu meters now using both stereo channels