Player Lobby UX Improvements

[bitoffdev]

The player lobby was originally created by #27, and selecting multiple opponents was added by #30. It works well functionally, but the UX is lacking.

Current Look

This is what the player lobby looks like.

Note: the style of the selected items (alpha and charlie) and the style of the current item (that the cursor is over) are very similar, which can be confusing to users. To be clear, "delta" is NOT selected in the above image, the cursor is just over it.

Requirements

1. The player lobby should not show the user their own name. It should only list the other players.
2. The player lobby should refresh the list of online users periodically.
3. The player lobby should not show users that are in-game, nor users that have disconnected.

Nice to Have

1. I'd like to see if we can replace the menu. We are currently using the curses menu library, but the multi-select is a bad user experience in my opinion. @bitoffdev tried many of the options for menu, but none of them improve the distinction between the current item and the selected items.
2. It would be cool if we could show the party to users as it is being built. ie. If charlie adds delta to his party, that should be reflected on delta's screen.
3. Party codes? Do we want to implement a code-based invite system?