(menu-bar-last-search-type): New var.

(menu-bar-last-search-type): New var.
(nonincremental-repeat-search-forward)
(nonincremental-repeat-search-backward): Repeat string or
regexp search depending on menu-bar-last-search-type.
(nonincremental-search-forward, nonincremental-re-search-forward)
(nonincremental-search-backward, nonincremental-re-search-backward):
Set menu-bar-last-search-type to string or regexp.
(nonincremental-repeat-re-search-forward): Removed.
(nonincremental-repeat-re-search-backward): Removed.
(menu-bar-replace-menu): New keymap for "Edit->Replace" submenu.
(menu-bar-i-search-menu): New keymap for "Incremental Search" submenu.
(menu-bar-adv-search-menu): Removed.
(menu-bar-search-menu): Reorganized.
(menu-bar-edit-menu): Added "Replace" submenu.