srb2::Vector: fix copy assignment not clearing contents of vector

- Test
  - debugwaypoints - very easily observable, all labels
	are the same without this fix
  - ACS text would sometimes be reversed without this fix,
	not as easily observable

src/core/vector.hpp

@@ -149,6 +149,7 @@ public:
 
 	Vector& operator=(const Vector& rhs)
 	{
+		clear();
 		for (auto itr = rhs.begin(); itr != rhs.end(); itr++)
 		{
 			push_back(*itr);