Select another window in cyclic ordering of windows.
COUNT specifies the number of windows to skip, starting with the
selected window, before making the selection. If COUNT is
positive, skip COUNT windows forwards. If COUNT is negative,
skip -COUNT windows backwards. COUNT zero means do not skip any
window, so select the selected window. In an interactive call,
COUNT is the numeric prefix argument. Return nil.
If the `other-window' parameter of the selected window is a
function and `ignore-window-parameters' is nil, call that
function with the arguments COUNT and ALL-FRAMES.
This function does not select a window whose `no-other-window'
window parameter is non-nil.
This function uses `next-window' for finding the window to
select. The argument ALL-FRAMES has the same meaning as in
`next-window', but the MINIBUF argument of `next-window' is
always effectively nil.