* module/web/client.scm (ensure-uri): New helper.
(open-socket-for-uri): Accept a URI as a string or as a URI object.
(extend-request, sanitize-request): New helpers, like the
corresponding functions in (web server).
(decode-response-body): Add a reference to the HTTP/1.1 spec, and
use (ice-9 iconv).
(request): New helper, factoring all aspects of sending an HTTP
request and getting a response.
(http-get): Redefine in terms of http-get. Deprecate the
#:extra-headers argument in favor of #:headers. Allow a body. Add a
#:streaming? argument, subsuming the functionality of http-get*.
(http-get*): Deprecate.
(http-head, http-post, http-put, http-delete, http-trace)
(http-options): Define interfaces for all HTTP verbs.
* test-suite/tests/web-client.test: Add tests.
* doc/ref/web.texi: Update documentation.
Thanks to Gregory Benison for the initial patch.
