Issues pointed out by the alpha

[Sylmir]

• Legacy installation should allow the choice between Vanilla and Repentogon through the -repentogone option -> Done
• Multiple synchronization issues between IsaacOptions and the GUI
• Source unknown : dsound version started from the launcher has corrupted save files (could be a multiple DLL loads issue) -> was a permission problem because Windows ?
• Source unknown : white screen freeze in RegisterClasses when starting modern Repentogon from the launcher -> Inconsistent Lua runtime due to redirection disabled
• GUI issue : high DPI (possibly) causes Advanced Options to be out of screen
• GUI issue : no scrollbar even if some options are not displayed on screen
• It is likely that the INIReader holds a lock on the configuration file and the file is being opened through multiple different handles. This may result in weird issues
• The launcher should check that it is able to read the savefiles and throw a warning (related to the above issue about corrupted files) -> won't do, Repentogon is more suited to do that
• Files are extracted nonsensically -> Fixed, missing a string concat
• Launcher crashes on startup -> Userenv.dll was unloaded, thus invalidating the calls to GetUserProfileDirectoryA
• Launcher should not assume the exe is called isaac-ng.exe -> Done
• Cancelling the selection of the isaac file destroys the content of the form -> Fixed, input is sanitized
• Launcher freezes when the game is started, until it ends