the code has up until now used shorthand var names such as bw
for bar width and lcf for lower cut-off frequency. There is no
need for this. We are now moving to a naming scheme of
descriptive names on two to three words using underscores.
Backwards incompatible change: cycle foreground color changed from 'c' to 'f'
so that color reload can be 'c'.
License: MIT
Signed-off-by: David Grisham <dgrisham@mines.edu>