po/.gitattributes

   1 # You should add
   2 #[filter "cleanpo"]
   3 #        clean = "awk '/^\"POT-Creation-Date:/&&!s{s=1;next};!/^#: /{print}'"
   4 # to your config file.
   5
   6 /??.po     filter=cleanpo
   7 /??_??.po  filter=cleanpo