Update features and introduction sections
Update features and introduction sections

tweak some other sections slightly too
jimmikaelkael/GlowstonePlusPlus,GreenBeard/GlowstonePlusPlus,BlazePowered/Blaze-Server,GlowstoneMC/GlowstonePlusPlus,keke142/GlowstonePlusPlus,Postremus/GlowstonePlusPlus,LukBukkit/GlowstonePlusPlus,keke142/GlowstonePlusPlus,Postremus/GlowstonePlusPlus,jimmikaelkael/GlowstonePlusPlus,LukBukkit/GlowstonePlusPlus,GlowstonePlusPlus/GlowstonePlusPlus,LukBukkit/GlowstonePlusPlus,GlowstonePlusPlus/GlowstonePlusPlus,GlowstonePlusPlus/GlowstonePlusPlus,GlowstoneMC/GlowstonePlusPlus,BlazePowered/Blaze-Server,LukBukkit/GlowstonePlusPlus,keke142/GlowstonePlusPlus,GreenBeard/GlowstonePlusPlus,GreenBeard/GlowstonePlusPlus,BlazePowered/Blaze-Server,GlowstonePlusPlus/GlowstonePlusPlus,BlazePowered/Blaze-Server,Postremus/GlowstonePlusPlus,keke142/GlowstonePlusPlus,GreenBeard/GlowstonePlusPlus,GlowstoneMC/GlowstonePlusPlus,Postremus/GlowstonePlusPlus,jimmikaelkael/GlowstonePlusPlus,jimmikaelkael/GlowstonePlusPlus,GlowstoneMC/GlowstonePlusPlus