Fix what's new popup and show it for each user if enabled

[cewert]

A recent PR broke the whats new popup so that it will show every login if enabled and the whats new user setting had a bug where it would only be respected if that user was the first to login after an upgrade. This fixes both of those issues.

Changes

• During 2.0.0 migration, set each users LastRunVersion to the app's LastRunVersion i.e. 1.6.6
• Use the user's lastrunversion when checking if we should show the whats new popup after login
• After login, update the users lastrunversion in the registry if it does not equal the apps current version
• Display the current app version in the whats new popup title
• Use the current app version as the filename for the whatsnew json data
  • This would allow us in the future to display a whats new popup for every version the user has missed

[1hitsong]

I did a clean install of 2.0.0 and the popup didn't show.