Make antsRegistration cmdline consistent with documentation

Author: Gilles86

nipype/interfaces/ants/registration.py

@@ -866,7 +866,7 @@ def _format_winsorize_image_intensities(self):
                                                              self.inputs.winsorize_upper_quantile)
 
     def _get_initial_transform_filenames(self):
-        retval = ['--initial-moving-transform']
+        retval = ['--initial-moving-transform ']
         for ii in range(len(self.inputs.initial_moving_transform)):
             if isdefined(self.inputs.invert_initial_moving_transform):
                 if len(self.inputs.initial_moving_transform) == len(self.inputs.invert_initial_moving_transform):