Merge branch 'feature/remove-warning' into 'master'

Comment out warnings

See merge request core/dune-istl!121

dune/istl/paamg/amg.hh

@@ -325,7 +325,7 @@ namespace Dune
         postSteps_(parms.getNoPostSmoothSteps()), buildHierarchy_(false),
         additive(parms.getAdditive()), coarsesolverconverged(true),
         coarseSmoother_(),
-#warning should category be retrieved from matrices?
+// #warning should category be retrieved from matrices?
         category_(SolverCategory::category(*smoothers_->coarsest())),
         verbosity_(parms.debugLevel())
     {

dune/istl/solver.hh

@@ -264,7 +264,7 @@ namespace Dune
         DUNE_THROW(InvalidSolverCategory, "LinearOperator and ScalarProduct must have the same SolverCategory!");
     }
 
-#warning actually we want to have this as the default and just implement the second one
+    // #warning actually we want to have this as the default and just implement the second one
     // //! \copydoc InverseOperator::apply(X&,Y&,InverseOperatorResult&)
     // virtual void apply (X& x, Y& b, InverseOperatorResult& res)
     // {