Lots of work on solvers

src/main/scala/inox/ast/Expressions.scala

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

src/main/scala/inox/solvers/Solver.scala

src/main/scala/inox/solvers/unrolling/DatatypeManager.scala

...main/scala/inox/solvers/unrolling/DatatypeTemplates.scala

...main/scala/inox/solvers/unrolling/FunctionTemplates.scala

src/main/scala/inox/solvers/unrolling/LambdaManager.scala

src/main/scala/inox/solvers/unrolling/LambdaTemplates.scala

src/main/scala/inox/solvers/unrolling/Quantification.scala

...cala/inox/solvers/unrolling/QuantificationTemplates.scala

src/main/scala/inox/solvers/unrolling/TemplateEncoder.scala

...main/scala/inox/solvers/unrolling/TemplateGenerator.scala

src/main/scala/inox/solvers/unrolling/TemplateInfo.scala

src/main/scala/inox/solvers/unrolling/TemplateManager.scala

src/main/scala/inox/solvers/unrolling/Templates.scala

src/main/scala/inox/solvers/unrolling/UnrollingBank.scala

src/main/scala/inox/solvers/unrolling/UnrollingSolver.scala

src/main/scala/inox/utils/IncrementalStateWrapper.scala