redirect: add redirect bit to rd, handle properly in diagram

[seliopou]

Previously, the code could not distinguish between a redirect and resource creation during POST or PUT processing. Users should use the Rd.redirect function to indicate that the request should be redirected while setting the Location header to the appropriate value.

[seliopou]

@slegrand45 can you confirm the fix?

[slegrand45]

I can confirm that i get a 201 now, without any modification in my code. Thank you very very much!