withUnification

Upgrades this :dsl-core scope into a :dsl-unify LogicProgrammingScope adding unification support to it, reusing its underlying it.unibo.tuprolog.core.Scope, it.unibo.tuprolog.dsl.Termificator and it.unibo.tuprolog.core.VariablesProvider (so it.unibo.tuprolog.core.Vars and terms already built through this scope remain valid and usable in the returned one) and equipping it with unificator (LogicProgrammingScope.defaultUnificator unless stated otherwise) as its unification strategy. Useful when a plain :dsl-core scope is already at hand (e.g. received as a parameter) and unification is only needed from that point on.