made compilation of ConstraintCollector in Dtmc predicated on CARL being available

Former-commit-id: 8d0e3ea636

src/models/sparse/Dtmc.cpp

@@ -182,6 +182,7 @@ namespace storm {
                 //		return storm::models::Dtmc<ValueType>(newMatBuilder.build(), newLabeling, newStateRewards, std::move(newTransitionRewards), newChoiceLabels);
             }
             
+#ifdef STORM_HAVE_CARL
             template<typename ValueType>
             Dtmc<ValueType>::ConstraintCollector::ConstraintCollector(Dtmc<ValueType> const& dtmc) {
                 process(dtmc);
@@ -221,6 +222,7 @@ namespace storm {
             void Dtmc<ValueType>::ConstraintCollector::operator()(storm::models::sparse::Dtmc<ValueType> const& dtmc) {
                 process(dtmc);
             }
+#endif
             
             template <typename ValueType>
             bool Dtmc<ValueType>::checkValidityOfProbabilityMatrix() const {

src/models/sparse/Dtmc.h

@@ -59,6 +59,7 @@ namespace storm {
                  */
                 Dtmc<ValueType> getSubDtmc(storm::storage::BitVector const& states) const;
                 
+#ifdef STORM_HAVE_CARL
                 class ConstraintCollector {
                 private:
                     // A set of constraints that says that the DTMC actually has valid probability distributions in all states.
@@ -118,6 +119,7 @@ namespace storm {
                  */
                 bool checkValidityOfProbabilityMatrix() const;
             };
+#endif
             
         } // namespace sparse
     } // namespace models