Merge pull request #496 from SyamGadde/patch-1

MRG: Format string {} not allowed in Python 2.6

At least allow Nibabel to work to some degree with Python 2.6, but expecting there to be more breakage down the road.

Author: matthew-brett

nibabel/deprecator.py

@@ -146,7 +146,7 @@ def __call__(self, message, since='', until='',
         if since:
             messages.append('* deprecated from version: ' + since)
         if until:
-            messages.append('* {} {} as of version: {}'.format(
+            messages.append('* {0} {1} as of version: {2}'.format(
                 "Raises" if self.is_bad_version(until) else "Will raise",
                 error_class,
                 until))