* src/config.c (backend_parse_servername): Don't require HTTPS.
ServerName can be used with plain HTTP backends as well.
* src/svc.c (need_rewrite): Rewrite from scratch.
* tests/poundharness.pl (http_redirect): Send original location in
X-Orig-Location header.
* tests/rewriteloc.at: Rewrite.
* tests/rewriteloc_https.at: New test.
* tests/testsuite.at: Include new test.
* tests/Makefile.am: Add new test.
* doc/pound.texi: Document changes.
