* [sdl2pp] no absolute paths
* [sdl2-image][sdl2-mixer][sdl2-ttf][sdl2pp] Install and fix .pc files
Co-authored-by: Robert Schumacher <roschuma@microsoft.com>
* Fix mpg123 build in macOS and Linux, fix sdl2-mixer find mpg123 libarry
* Add package sdl2pp
* [mpg123] Use Windows logic in Windows Desktop
* [sdl2-mixer] Bump package version
* [sdl2pp] Use patch instead of replacing CMakeLists.txt. Use vcpkg_from_github()