Allow ILaunchHandlerServices to decide whether to use early display.

[heipiao233]

Till now, early display is used only when launch target is neoforgeclient and neoforgeclientdev. However third-party guys may want to use it with their launch targets.
In ModLauncher, launch targets are constructed very early when Launcher constructs, and early display is loaded on ModDirTransformerDiscoverer.earlyInitialization (Is that really good?), which is constructed when Launcher runs. So it's possible to do so.