Resolve "IsMotion used in Problem::getState()"

Closes #399 (closed)

include/core/state_block/state_composite.h

@@ -69,13 +69,7 @@ class VectorComposite : public std::unordered_map < char, Eigen::VectorXd >
         void set(const VectorXd& _v, const StateStructure& _structure, const std::list<int>& _sizes);
         void setZero();
 
-        bool includesStructure(const StateStructure& _structure)
-        {
-            for (auto key : _structure)
-                if (count(key) == 0)
-                    return false;
-            return true;
-        }
+        bool includesStructure(const StateStructure &_structure) const;
 
         friend std::ostream& operator <<(std::ostream &_os, const wolf::VectorComposite &_x);
         friend wolf::VectorComposite operator +(const wolf::VectorComposite &_x, const wolf::VectorComposite &_y);