avg_q_ui/avg_q_ui.c: Merged removal of unnecessary menu separators at the top
of each menu
python/avg_q/Artifacts.py: Fixed moving of channel_list2arg to avg_q
module function
Measure.py: Add output_comment option
bf/subtract.c: Merged changed item-wise behavior also where leaveright>0,
'average'-like summation of leaveright values in -mean or -wmean mode,
and the corresponding documentation in Documentation/Programs_handbook.lyx