bug#12943: 24.2.50; switch to help buffer with > 3-window-split

[martin rudalics]

> Hm, the default 'other of help-window-select is inconsistent and aims a
> very specific user pattern.

The idea behind the default is:

(1) If the help window is the only other window on the frame, you can
    type C-x o q to restore the state before invoking help.

(2) If the help buffer is shown in a third or fourth window, there's no
    obvious key sequence to do that.  If, however, the help window gets
    selected, typing "q" will do.

> I might want to keep the help window open for long and keep working on
> my code while referencing the help. This is my 99% usage pattern.

In this case setting `help-window-select' to nil should do what you
want.

> Now, when I open the help buffer I have to switch back to my working
> window all the way back through 3 other windows. Awful.

If and when we get the C-x 4 prefix working, we can simplify things by
setting C-x 4 q to quit the last window that can be quit.  Till then,
customizing `help-window-select' should be an acceptable solution.

martin