mod_rewrite:Fix query string handling for proxied URLs.

PR:	14518
Obtained from:
Submitted by:
Reviewed by:	nd, minfrin, jim


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@105443 13f79535-47bb-0310-9956-ffa450edef68