fixed a small typo in the Utilities/__init__.py file (a period was missing in the import statment).

proxtoolbox/Utilities/__init__.py

@@ -7,6 +7,6 @@ Created on Thu Jan 28 14:10:51 2016
 The "Utilities"-module contains various ...
 """
 
-from Laplace_matrix import *
+from .Laplace_matrix import *
 
 __all__ = ["Laplace_matrix"]