(ido-read-internal): Don't set ido-default-item if the default is
member of ido-ignore-item-temp-list.
Don't return first match for C-j if no text is entered.
(ido-buffer-internal): Check for empty string return.
(ido-make-buffer-list1): Use member instead of memq.
(ido-window-buffer-p): Likewise.
(ido-get-bufname): Ignore buffers on ido-ignore-item-temp-list.
(ido-ignore-item-p): Ignore items on ido-ignore-item-temp-list.
