BF - test-failure in TestHilberAnalyzer. Closes #4.

This is due to a bug in scipy.signal in r<6205. Made sure that no
scipy 0.8 uses scipy.signal.hilbert, but instead just the version of
hilbert that we ship in the utils.

nitime/analysis.py

@@ -989,7 +989,7 @@ def output(self):
         data = self.input.data
         sampling_rate = self.input.sampling_rate
         #If you have scipy with the fixed scipy.signal.hilbert (r6205 and later)
-        if float(scipy.__version__[:3])>=0.8:
+        if scipy.__version__>='0.9':
             hilbert = signal.hilbert
         else:
             hilbert = tsu.hilbert_from_new_scipy