Backport r104934:

Allow for the use of --with-module=foo:bar where the ./modules/foo
directory is local only. Assumes, of course, that the required
files are in ./modules/foo, but makes it easier to statically
build/log "external" modules.



git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.0.x@124543 13f79535-47bb-0310-9956-ffa450edef68