This change is only relevant for Windows 8, 8.1, and RT apps, and only for those that are network-enabled. Such apps must feature a link to a privacy policy, which must be displayed via the Windows Settings charm. This is needed to pass Windows Store app-certification.
Using SDL_SetHint, along with SDL_HINT_WINRT_PRIVACY_POLICY_URL and optionally SDL_HINT_WINRT_PRIVACY_POLICY_LABEL, will cause SDL/WinRT to create a link inside the Windows Settings charm, as invoked from within an SDL-based app.
Network-enabled Windows Phone apps do not need to set this hint, and should provide some sort of in-app means to display their privacy policy. Microsoft does not appear to provide an OS-integrated means for displaying such on Windows Phone.
This change removes some code that attempted to allow non-standard window sizes, the idea of which was to do display scaling, and a hackish one at that. If display scaling is needed, use SDL_Renderer as appropriate.
- moved SDL_WinRTApp.* from src/video/windowsrt/ to src/core/winrt/, and renamed them to SDL_winrtapp.* (to mimick case-sensitivity used elsewhere in SDL)
- renamed all "windowsrt" directories (in src) to "winrt", as the shorthand name is used more often (and, IMO, "WinRT" != "Windows RT", not entirely at least)
