mod_alias: Accept path components (URL part) in Redirects. PR 35314.

(Backport of r490142)

Reviewed by: niq, jim, wrowe


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.2.x@539273 13f79535-47bb-0310-9956-ffa450edef68