Fix the fixes

src/main/scala/leon/aographs/Graph.scala

src/main/scala/leon/synthesis/Cost.scala

src/main/scala/leon/synthesis/Problem.scala

src/main/scala/leon/synthesis/Rules.scala

src/main/scala/leon/synthesis/Solution.scala

src/main/scala/leon/synthesis/SynthesisPhase.scala

src/main/scala/leon/synthesis/Synthesizer.scala

src/main/scala/leon/synthesis/rules/Cegis.scala