Improved documentation

[ci skip]

README.md

@@ -137,7 +137,7 @@ Set up (the latest version of) [HAProxy](http://www.haproxy.org/) in Ubuntu syst
 * `haproxy_frontend.{n}.http_response.{n}.action`: [required]: The rules action (e.g. `del-header`)
 * `haproxy_frontend.{n}.http_response.{n}.param`: [optional]: The complete line to be added (e.g. `X-Varnish`)
 * `haproxy_frontend.{n}.http_response.{n}.cond`: [optional]: A matching condition built from ACLs
-* `haproxy_frontend.{n}.use_backend`: [optional]: Switch to a specific backend if/unless a Layer 7 condition is matched. (e.g. '%[req.hdr(host),lower,map_dom(/etc/haproxy/haproxy_backend.map,bk_default)]')
+* `haproxy_frontend.{n}.use_backend`: [optional]: Switch to a specific backend if/unless a Layer 7 condition is matched. (e.g. '%[req.hdr(host),lower,map_dom(/etc/haproxy/haproxy_backend.map,bk_default)]' or `['foo-backend if is_foo', 'bar-backend if is_bar']`)
 * `haproxy_frontend.{n}.default_backend`: [required]: The backend to use when no `"use_backend"` rule has been matched (e.g. `webservers`)
 * `haproxy_frontend.{n}.rspadd`: [optional]: Adds headers at the end of the HTTP response
 * `haproxy_frontend.{n}.rspadd.{n}.string`: [required]: The complete line to be added. Any space or known delimiter must be escaped using a backslash (`'\'`) (in version < 1.6)