Update release instructions to remove ref to doc/NEWS.txt

doc/internal/how_to_release.txt

@@ -11,9 +11,6 @@ Update the NEWS.txt and move the old stuff in the HISTORY.txt file.
 To update the NEWS.txt file, check all ticket closed for this release
 and all commit log messages. Update the index.txt *News* section.
 
-For the final release, copy the file ``Theano/NEWS.txt`` to
-``Theano/doc/NEWS.txt``.
-
 Update the "Vision"/"Vision State" in the file
 ``Theano/doc/introduction.txt``.