Change constructor to take pointers instead of references

This is done to make constructors consistent accross the algorithms.

Src/Adaptive/new/FAdaptiveStarPU.hpp

@@ -48,9 +48,9 @@ private:
 
 public:
 
-    FAdaptiveStarPU(tree_t& tree, kernel_t& kernel) :
-        _tree(tree),
-        _ref_kernel(kernel),
+    FAdaptiveStarPU(tree_t* tree, kernel_t* kernel) :
+        _tree(*tree),
+        _ref_kernel(*kernel),
         _kernels()
     {}