add processor_ptr_ in ConstraintBase

Add ProcessorBaseWPtr processor_ptr_ in ConstraintBase.

Pointer is set at construction time, all derived classes have been updated together with processors.

ConstraintBase and derived now take argument pointers by const references rather than copy.

Bonus: A few c++11 keywords here and there.

src/examples/test_constraint_AHP.cpp

@@ -43,7 +43,7 @@ int main()
 
     // PROCESSOR
     // one-liner API
-    wolf_problem_ptr_->installProcessor("IMAGE LANDMARK", "ORB", "PinHole", wolf_root + "/src/examples/processor_image_ORB.yaml");
+    ProcessorBasePtr processor_ptr = wolf_problem_ptr_->installProcessor("IMAGE LANDMARK", "ORB", "PinHole", wolf_root + "/src/examples/processor_image_ORB.yaml");
 
 
     // create the current frame
@@ -118,7 +118,7 @@ int main()
 
 
     // Create the constraint
-    ConstraintAHPPtr constraint_ptr = std::make_shared<ConstraintAHP>(feat_point_image_ptr, std::static_pointer_cast<LandmarkAHP>(landmark));
+    ConstraintAHPPtr constraint_ptr = std::make_shared<ConstraintAHP>(feat_point_image_ptr, std::static_pointer_cast<LandmarkAHP>(landmark), processor_ptr);
 
     feat_point_image_ptr->addConstraint(constraint_ptr);
     std::cout << "Constraint AHP created" << std::endl;