here applies the same. Don't skip the \0 delimiter when searching

for already applied encodings. Additionally don't compress if *any*
non-identity encoding was applied before. (deflate, pkzip, whatever).


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@101019 13f79535-47bb-0310-9956-ffa450edef68