Apply BSD 2 clauses license

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

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

...main/scala/leon/synthesis/rules/UnconstrainedOutput.scala

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

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

src/main/scala/leon/synthesis/search/AndOrGraph.scala

.../scala/leon/synthesis/search/AndOrGraphDotConverter.scala

...cala/leon/synthesis/search/AndOrGraphParallelSearch.scala

...ala/leon/synthesis/search/AndOrGraphPartialSolution.scala

src/main/scala/leon/synthesis/search/AndOrGraphSearch.scala

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

src/main/scala/leon/synthesis/utils/Benchmarks.scala

...eon/synthesis/utils/SynthesisProblemExtractionPhase.scala

src/main/scala/leon/termination/SCC.scala

...ain/scala/leon/termination/SimpleTerminationChecker.scala

src/main/scala/leon/termination/TerminationChecker.scala

src/main/scala/leon/termination/TerminationPhase.scala

src/main/scala/leon/termination/TerminationReport.scala

src/main/scala/leon/testgen/CallGraph.scala

src/main/scala/leon/testgen/TestGeneration.scala