Encourage level restarts on very_old_saves

[lewri]

Proposal to give the option to the user to restart their level for very old saves compared to just information.
This method might be too assertive on the player so it can be dropped if it's going to be too far.

Describe what the proposed change does

• Changes this UIInformation to a UIConfirmDIalog for old saves.
• Adapts App:restart() to take an optional message for the box

[lewri]

If we wanted to go ahead then I can ask our translators for strings if needed as this is an important message.

[TheCycoONE]

Good idea. I would leave off the first "this level"

A few comments:
new-20 is a bit arbitrary, sometimes we'd eat through more than that in a single version, maybe we can do something with the release table we're maintaining in TheApp (currently a giant if condition).

I'm not sure this shouldn't be built into the existing TheApp.checkCompatibilty handling (see that function and peristence.lua where it's called)

[lewri]

new-20 is a bit arbitrary, sometimes we'd eat through more than that in a single version, maybe we can do something with the release table we're maintaining in TheApp (currently a giant if condition).

Struggling with ideas on this one currently. Really for a good flexible comparison the function needs to be redesigned in a way that reports a better testable case so handle e.g. current release - 2. Generally speaking, that means we flag for 0.65 being loaded in 0.68 and so on. But say we skipped to 0.70 this release, then it still needs to flag against 0.65 rather than 0.67
(Then we also need to decide what to do with Trunk)

[lewri]

Good idea. I would leave off the first "this level"

A few comments: new-20 is a bit arbitrary, sometimes we'd eat through more than that in a single version, maybe we can do something with the release table we're maintaining in TheApp (currently a giant if condition).

I'm not sure this shouldn't be built into the existing TheApp.checkCompatibilty handling (see that function and peristence.lua where it's called)

Pushed the string change for now.
In regards to versions I've started #2527 as my planned changes will probably deserve their own PR separate to this. If you want to hold back the PR still until that's done that's fine.