Originally space was thought out to also accept the selection, but only
a broken binding was added. As we want to use space for selections in
the future we now remove it entirely.
If the user only supplys a text for the option we used to return None as
item value. Now we return the text, so the user can easily get the value
back if they want to process it further and not only work with the given
option index (or supply the item twice).
get_options() and num_options used to work on all menu items, including
blank spaces and headers. Now these work only on options, as they were
originally intended
cli_select_item() allows to quickly launch a menu from code, but if only
a single item is given a selection is not necessary in most cases.
Therefore we now instantly return the given value in these cases. This
can be turned off by setting return_single=False
This uses prompt-toolkit's builtin search functionality to search
through the buffer representing the menu, allowing the user
to navigate faster through the entries