Fixes <http://bugs.gnu.org/14370>.
Reported by Atom X Zane <atomx@deadlyhead.com>.
* module/web/http.scm (write-credentials): Handle the Basic auth scheme
correctly.
* test-suite/tests/web-http.test (pass-if-round-trip): Use
'pass-if-equal' for better error reporting.
("request headers"): Add tests.
* THANKS: Add "Atom X Zane" to bug fix section.