[Num/ODE] add documentation

NumLib/ODESolver/ConvergenceCriterionPerComponentResidual.h

@@ -36,6 +36,8 @@ public:
     bool hasDeltaXCheck() const override { return true; }
     bool hasResidualCheck() const override { return true; }
 
+    /// The function will only do diagnostic output and no actual check of the
+    /// solution increment is made
     void checkDeltaX(const GlobalVector& minus_delta_x,
                      GlobalVector const& x) override;
     void checkResidual(const GlobalVector& residual) override;