Make the choice between gui-v1 and gui-v2 work well

[mpvader]

For the first official release of gui-v2, which will be part of v3.50, we'll keep gui-v1 to be the default onscreen display. And it will show a popup for the user to switch to gui-v2 (on the platforms that support that, ie Cerbo and Ekrano).

What needs to be done is:

• [ ] decide if we stick to the terms "gui-v1" and "gui-v2" or can we come up with something better?
• [ ] gui-v1: remove the use of the word beta (@jhofstee )
• [ ] gui-v2: remove the use of the word beta (Qinetic, see screenshots below for how it looks now )
• [ ] fix wording and things in VRM (El Nino)
• [ ] gui-v1: show a toast before stopping it, when switching to gui-v2. (@jhofstee )
• [ ] gui-v1: show a popup to tell people about gui-v2 (@jepefe ). Some ideas: here is are new gui, scan this qr code to read the blog about it. and also somewhere note that in case there are issues, there is an option, for now, to still use the old one, and here is where to find that.

[mpvader]

[mpvader]

and this is how it now looks in gui-v1