Preparation for commenting out unnecessary CPP language extension

+ Sorted language extensions
+ Removed duplicates
Merge branch 'maint-2.4.0'

Conflicts:
	src/full/Agda/Auto/NarrowingSearch.hs
	src/full/Agda/Interaction/InteractionTop.hs
	src/full/Agda/Interaction/Options.hs
	src/full/Agda/Syntax/Translation/ConcreteToAbstract.hs
	src/full/Agda/Termination/CallGraph.hs
	src/full/Agda/Termination/Inlining.hs
	src/full/Agda/Termination/Monad.hs
	src/full/Agda/Termination/SetOfCallsCallGraph.hs
	src/full/Agda/Termination/TermCheck.hs
	src/full/Agda/TypeChecking/CheckInternal.hs
	src/full/Agda/TypeChecking/CompiledClause/Match.hs
	src/full/Agda/TypeChecking/DropArgs.hs
	src/full/Agda/TypeChecking/MetaVars.hs
	src/full/Agda/TypeChecking/Patterns/Abstract.hs
	src/full/Agda/TypeChecking/Reduce/Monad.hs
	src/full/Agda/TypeChecking/SizedTypes/Solve.hs
	src/full/Agda/TypeChecking/SizedTypes/WarshallSolver.hs