If you're using the github version of Navigator, please update

[Geoff Canyon]

Turns out I had a glitch I didn't notice with my github client, and no
updates were making it to main for some time now. So if you happen to have
installed Navigator by cloning the repo, now would be a good time to
update. Some improvements that have happened:

1. I  completely did away with the stack and card menus, replacing them
with a single Target menu (indicated by a bullseye). It lists every stack
with a submenu that includes things like Go (goes to the stack), Toplevel
(Toplevels the stack), Card List and Background List, and further submenus
for the cards and backgrounds, allowing you to focus on any of them.  This
fixes several small issues with the previous stack and card target menus.

Remember that Navigator can display multiple targets if you hold down the
Shift key while choosing a target -- you can have as many as you like,
subject to performance limitations.

Note: if anyone finds this menu to be too slow, let me know -- it does
count through all cards and backgrounds of every stack, but in my
experience unless you're dealing with literally tens of thousands of cards
it should be fine. I could write some sort of caching algorithm and make
updates manual -- or something, I haven't thought about it too much.

2. I improved the The MouseStack targeting functionality. I don't know what
I was thinking before with the usability of the click, or long-click, on
the menu. So at this point the menu is just a menu -- select "the
mouseStack" on the menu and you get the pointer bullseye, then click over
whatever target you like to select it in Navigator.

3. I switched to the merge function for the custom list display string.
This opens up a ridiculous set of possibilities if anyone cares to really
dig in.

If you find any bugs let me know.