[exercise-properties]

removed Task 3; Properties::print<TypeTag>(); doesn't exist anymore

exercises/exercise-properties/README.md

@@ -47,20 +47,9 @@ make exercise_properties
 Note: Because the input file has the same name as the
 executable, DuMu<sup>x</sup> will find it automatically.
 
-<hr><br><br>
-### Task 3: Inspect the type tag tree
-<hr>
-
-Many types in DuMu<sup>x</sup> are properties that are attached to property tags which themselves are attached to type tags.
-To view the complete type tag tree, add the line
-```
-Properties::print<TypeTag>();
-```
-directly above the `return 0;` statement of the main function.
-Inspect the result.
 
 <hr><br><br>
-### Task 4: Implement a custom local residual
+### Task 3: Implement a custom local residual
 <hr>
 
 Types that are properties can be changed on the problem level by using the property system. In the following task we implement our own 2p local residual, i.e. the class that computes the element residual  in every Newton iteration. The file `mylocalresidual.hh` contains a copy of the original local residual class used for all immiscible models renamed to `template<class TypeTag> class MyLocalResidual`.
@@ -75,7 +64,6 @@ struct LocalResidual<TypeTag, TTag::TwoPIncompressible>
     using type = MyLocalResidual<TypeTag>;
 };
 ```
-Observe the difference in the output of the type tag tree.
 
 Simplify the original local residual by using the assumption that only incompressible fluid phases are present. As a consequence, one can balance phase volume instead of phase mass: