add task about SolverResult; collect all MultigridStep related todos

[[Imported from SVN: r7353]]

TODO

@@ -37,19 +37,19 @@ and maintain.
 * Implement (P)CG as IterationStep for the LoopSolver
 * Make all public member variables protected and introduce public methods for access.
 * Use references instead of pointers as member function arguments.
-* Move stuff done in MultigridStep::setNumberOfLevels() into preprocess().
 * Make handling solution vector in IterationStep consistent:
   Either provide a const reference, store a copy and give (reference)
-  access to this copy using getSol() or provide a (nonsonst) reference,
+  access to this copy using getSol() or provide a (nonconst) reference,
   store the solution there and make getSol() return this reference
   and no copy.
   (C: I'd prefer the latter to reduce the number of vector copies).
-* Make setting up a MultigridStep easier. E.g. by providing a default
-  version that is preconfigured with GS smoother and coarse grid solver.
+* Move stuff done in MultigridStep::setNumberOfLevels() into preprocess().
 * Remove MultigridStep::setNumberOfLevels(), this number is already
   fixed by the size of the transfer operator vector.
 * MultigridStep hides member names from the base class by reusing
   them for different things
+* Make setting up a MultigridStep easier. E.g. by providing a default
+  version that is preconfigured with GS smoother and coarse grid solver.
 * MultigridStep works differently on the finest and the other
   levels. On the finest, the smoother is used with the rhs of
   the linear system and the current iterate as initial value
@@ -60,7 +60,9 @@ and maintain.
   Computing corrections also on the finest level might allow
   to solve systems really up to machine accuracy sice you
   have more digits for the correction.
-  
+* devise a coherent meaningful concept of a SolverResult struct for the various
+  Solver Base-classes (Solver, IterativeSolver, LoopSolver atl) and substitute the 
+  q&d version implemented now
 
 
 ## Naming of classes and members