New And/Or Search Strategies

src/main/scala/leon/synthesis/PartialSolution.scala

src/main/scala/leon/synthesis/Search.scala

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

src/main/scala/leon/synthesis/graph/DotGenerator.scala

src/main/scala/leon/synthesis/graph/Graph.scala

src/main/scala/leon/synthesis/graph/Search.scala

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

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

...ain/scala/leon/synthesis/strategies/BoundedStrategy.scala

...n/scala/leon/synthesis/strategies/CostBasedStrategy.scala

...main/scala/leon/synthesis/strategies/ManualStrategy.scala

src/main/scala/leon/synthesis/strategies/Strategy.scala

...scala/leon/synthesis/strategies/TimeSlicingStrategy.scala

...ain/scala/leon/synthesis/strategies/WrappedStrategy.scala

...test/scala/leon/regression/synthesis/SynthesisSuite.scala