MEDIUM: http-ana: Set termination state before returning haproxy response
When, for any reason and at any step, HAProxy decides to interrupt an HTTP
transaction, it returns a dedicated responses to the client (possibly empty)
and it sets the stream flags used to produce the session termination state.
These both operation were performed in any order, depending on the code
path. Most of time, the HAPRoxy response is produced first.
With this patch, the stream flags for the termination state are now set
first. This way, these flags become visible from http-after-reponse rule
sets. Only errors when the HAProxy response is generated are reported later.