Trac #17769: sage -n ipython broken

From 6.5.rc0 on,
{{{
    sage -n ipython
}}}
does no longer work, it starts the sagenb notebook with directory
`ipython.sagenb`.

Until 6.5.beta6, this opened the ipython notebook.

`sage -n -h` says:
{{{
   --notebook [NOTEBOOK], -n [NOTEBOOK], -notebook [NOTEBOOK]
                        The notebook to run [one of: default, ipython,
                        sagenb]. Default is sagenb
}}}
`sage -h` says
{{{
  -n, --notebook      -- shortcut for --notebook=default
}}}

So these two bits of documentation contradict each other and we have a
change of
behaviour.

URL: http://trac.sagemath.org/17769
Reported by: cheuberg
Ticket author(s): Volker Braun
Reviewer(s): François Bissey

src/bin/sage

@@ -638,9 +638,8 @@ if [[ "$1" =~ ^--notebook=.* || "$1" =~ ^-n=.* || "$1" =~ ^-notebook=.* ]] ; the
 fi
 
 if [ "$1" = "-notebook" -o "$1" = '--notebook' -o "$1" = '-n' ]; then
-    shift
     sage-cleaner &>/dev/null &
-    exec sage-notebook --notebook=default "$@"
+    exec sage-notebook "$@"
 fi
 
 if [ "$1" = "-bn" -o "$1" = "--build-and-notebook" ]; then