Merge branch 'bug_apply_topup' into 'master'

--imain in topup can take multiple filenames

See merge request fsl/fslpy!324

fsl/wrappers/eddy.py

@@ -92,7 +92,8 @@ def applytopup(imain, datain, index, **kwargs):
     }
 
     asrt.assertFileExists(datain)
-    asrt.assertIsNifti(imain)
+    for fn in imain.split(','):
+        asrt.assertIsNifti(fn)
 
     cmd  = [
         'applytopup', '--imain={}'.format(imain),