[devtools] make return value of get_response_header(raw=True) consistent wrt get_header(raw=True)
i.e. get_response_header(raw=True) now returns the first element of the list rather
than the list itself.
include *.pyinclude */*.pyrecursive-include data *.gif *.png *.ico *.css *.jsrecursive-include i18n *.porecursive-include wdoc *