changed unique1d to unique due to numpy refactoring in numpy 1.5.

bolt/io.py

@@ -98,7 +98,7 @@ def __init__(self, dim, instances, labels, qids = None):
         """The array holding the labels. """
         self._idx = np.arange(self.n)
         """The indexing array. """
-        self.classes = np.unique1d(labels)
+        self.classes = np.unique(labels)
         """The classes. """
 	self.qids = qids