Support rewrite-redirection-host for status code 303

[JohnWu-Pro]

In setRedirectHostRewrite of lib/http-proxy/passes/web-outgoing.js, only status code 301, 302, 307, 308 are supported. Status code 303 should also be supported.

Or, even better, make the list of eligible/desired redirect status code configurable.

[kooshywoosh]

+1 in my case, would like this for 401 as well

[jrnail23]

related issue #845: Add support of 303 to hostRewrite option