Compatibility with terminals/keyboards lacking some extended keys.

The following are now equivalanet in ulist (menus) and string input:
^B = home
^E = end
^V = insert (string input only)
^Z = help (F1)
and in menus only:
+ = insert
- = delete
backspace = escape (not new)
^U = pgup
^D = pgdn
^C = copy (F5)
^V = paste (F6)