Delete the blank world if it is found & add better rendering for when no worlds are added

[Hubcapp]

The automatically created Blank World (aka 01_World_1.ini) serves no one. It was a misguided addition intended to give players a blank slate to fill in connection details in the Settings dialogue. In actuality though, it makes it harder to understand that you have not correctly configured it to a working server, with the appearance that it is Set Up to connect to "World 1".

It also gives RSC+ the appearance of being a private server client, since players not interested in connecting to a live server may believe it is set up to do so.

We should:

1. Remove the code relating to creation of this file from RSC+
2. Add code which detects a file called 01_World_1.ini with no connection details filled in on boot, and delete it if found
3. Revise the login screen to not include the text World (Click to change): if no worlds are added
4. Revise the login screen to not include the Signup button if no world is selected
5. Instead of "Click here to login", the text could say "Click here to choose Replay"
6. Revise the "You need a members account to use this server" text.

And possibly more revisions could be made. This is to better emphasize the "Preservation Platform" side of RSC+ for those who do not use RSC+ to connect to a private server, possibly as part of the upcoming Native Binaries release.

With the "Blank World", the idea was to emphasize the possibility that RSC+ could connect to a server if there was one compatible (It was the anticipated RSCMinus server at the time), and for local development purposes. It has definitely outgrown any usefulness that it may have had, however, and it must go.

[Hubcapp]

Currently it is created in initWorlds(), in Settings.java, with the line createNewWorld(1);

[conker-rsc]

Thanks for the suggestion -- I will be doing this as part of my currently in-progress binaries work, given that I'm already making rather large changes to much of the related Worlds code.

[conker-rsc]

@Hubcapp

In the case when no worlds are configured,

Instead of "Click here to login", the text could say "Click here to choose Replay"

Does this mean the button should act as the "play" button does to take you to the file selection?

[conker-rsc]

Some more thoughts -- the welcome panel already contains the -server replay- block, so it seems a bit duplicative to keep it in, if you did want to change the text and functionality of the Click here to login button:

Additionally, I've made it such that login attempts without a configured world would invoke the existing following text, so perhaps that's enough to explain the UX here?

Ie. any login attempts would be thwarted with an explanation, and the two existing play buttons might be enough to guide the replay functionality?

(The rest of the items have been completed, in my WIP branch)