Removed references to Leon in Inox source

CODING_GUIDELINES.md

src/main/scala/inox/InoxOptions.scala

src/main/scala/inox/Reporter.scala

src/main/scala/inox/ast/ExprOps.scala

src/main/scala/inox/ast/Extractors.scala

src/main/scala/inox/ast/SymbolOps.scala

src/main/scala/inox/evaluators/RecursiveEvaluator.scala

src/main/scala/inox/solvers/SolverFactory.scala

src/main/scala/inox/solvers/smtlib/SMTLIBTarget.scala

src/main/scala/inox/solvers/z3/AbstractZ3Solver.scala

src/main/scala/inox/utils/Bijection.scala

src/main/scala/inox/utils/InterruptManager.scala

unmanaged/64/vanuatoo_2.11-0.1.jar