remove redundant KeyVector definition

gtsam/gtsam.i

@@ -66,27 +66,6 @@ class KeySet {
   void serialize() const;
 };
 
-// Actually a vector<Key>
-class KeyVector {
-  KeyVector();
-  KeyVector(const gtsam::KeyVector& other);
-
-  // Note: no print function
-
-  // common STL methods
-  size_t size() const;
-  bool empty() const;
-  void clear();
-
-  // structure specific methods
-  size_t at(size_t i) const;
-  size_t front() const;
-  size_t back() const;
-  void push_back(size_t key) const;
-
-  void serialize() const;
-};
-
 // Actually a FastMap<Key,int>
 class KeyGroupMap {
   KeyGroupMap();