Merge branch 'fix/addmissing-fvectorheader-insolution' into 'master'

Add missing header in model solution exercise

See merge request !217

(cherry picked from commit ffc66a93)

42cc33cc Add missing header in model solution exercise

exercises/solution/exercise-model/model.hh

@@ -23,6 +23,7 @@
 // In the file `model.hh`, we define the volume variables, the model equations, and
 // set all default model properties.
 
+#include <dune/common/fvector.hh>
 #include <dumux/common/math.hh>
 #include <dumux/common/properties.hh>
 #include <dumux/common/numeqvector.hh>