+ OwningVector, and other cleanup in view of pybind11

Base/Types/OwningVector.h

@@ -22,6 +22,7 @@
 
 #include <vector>
 #include <cstddef>
+#include <utility>
 
 //! A vector of unique pointers to objects that are cloneable.
 //!
@@ -49,7 +50,7 @@ public:
         if (this == &other)
             return *this;
         OwningVector ret(other);
-        swap(*this, ret);
+        std::swap(*this, ret);
         return *this;
     }