Since we use C++11, we should switch over to using std::unique_ptr when C++11 is being used. To do this, we follow what we have done for shared pointers and we define a STD_UNIQUE_PTR macro that can be used and it will "do the right thing". Due to some API differences in std::unique_ptr and due to the fact that we need to be able to compile without C++11, we can't use move semantics so some code needed to change so that it can compile with either C++.

Anyone wanting to use a unique_ptr or auto_ptr should now use the "STD_UNIQUE_PTR(TYPE)" macro.

llvm-svn: 179779