[WIP] Feature/solverfactory

This MR mainly contains the factory implementation from !5 (closed) with some cleanup:

• Allow creating solvers / preconditioners from ParameterTrees.

• A solver (including preconditioner) can now be configured via an ini file like this:

[solver]
precond = SeqSSOR
solver = CGSolver

[SeqSSOR]
iterations = 1
relaxation = 1.8

[CGSolver]
reduction=1e-9
maxit = 5000
verbose = 3

• The corresponding dune code currently looks like this:

auto solver = SolverPrecondFactory::create<VectorType> (matrix, configuration, "solver");

• Both the actual type of the solver/preconditioner and their parameters can chosen in the ini file.
• It is also possible to create only a solver or only a preconditioner this way. See the factory doxygen for details.

This MR depends on !84 (merged).

Note: change target branch to master, once !84 (merged) is merged!

dune/istl/novlpschwarz.hh

@@ -242,96 +242,16 @@ namespace Dune {
 
   /** @} */
 
-  /**
-   * @addtogroup ISTL_SP
-   * @{
-   */
-  /**
-   * \brief Nonoverlapping Scalar Product with communication object.
-   *
-   * Consistent vectors in interior and border are assumed.
-   */
-  template<class X, class C>
-  class NonoverlappingSchwarzScalarProduct : public ScalarProduct<X>
-  {
-  public:
-    //! \brief The type of the domain.
-    typedef X domain_type;
-    //!  \brief The type of the range
-    typedef typename X::field_type field_type;
-    //!  \brief The real-type of the range
-    typedef typename FieldTraits<field_type>::real_type real_type;
-    //! \brief The type of the communication object
-    typedef C communication_type;
-
-    /*! \brief Constructor
-     * \param com The communication object for syncing owner and copy
-     * data points. (E.~g. OwnerOverlapCommunication )
-     */
-    NonoverlappingSchwarzScalarProduct (const communication_type& com)
-      : communication(com)
-    {}
-
-    /*! \brief Dot product of two vectors.
-       It is assumed that the vectors are consistent on the interior+border
-       partition.
-     */
-    virtual field_type dot (const X& x, const X& y)
-    {
-      field_type result;
-      communication.dot(x,y,result);
-      return result;
-    }
-
-    /*! \brief Norm of a right-hand side vector.
-       The vector must be consistent on the interior+border partition
-     */
-    virtual real_type norm (const X& x)
-    {
-      return communication.norm(x);
-    }
-
-    //! Category of the scalar product (see SolverCategory::Category)
-    virtual SolverCategory::Category category() const
-    {
-      return SolverCategory::nonoverlapping;
-    }
-
-    /*! \brief make additive vector consistent
-     */
-    void make_consistent (X& x) const
-    {
-      communication.copyOwnerToAll(x,x);
-    }
-
-  private:
-    const communication_type& communication;
-  };
-
-  template<class X, class C>
-  struct ScalarProductChooser<X,C,SolverCategory::nonoverlapping>
-  {
-    /** @brief The type of the scalar product for the nonoverlapping case. */
-    typedef NonoverlappingSchwarzScalarProduct<X,C> ScalarProduct;
-    /** @brief The type of the communication object to use. */
-    typedef C communication_type;
-
-    enum {
-      /** @brief The solver category. */
-      solverCategory=SolverCategory::nonoverlapping
-    };
-
-    static ScalarProduct* construct(const communication_type& comm)
-    {
-      return new ScalarProduct(comm);
-    }
-  };
-
   namespace Amg
   {
     template<class T> class ConstructionTraits;
   }
 
+  /**
+   * @addtogroup ISTL_Prec
+   * @{
+   */
+
   /**
    * @brief Nonoverlapping parallel preconditioner.
    *