Cancel keepalive and lingering close on EOF better (ticket #2145). Unlike in 75e908236701, which added the logic to ngx_http_finalize_request(), this change moves it to a more generic routine ngx_http_finalize_connection() to cover cases when a request is finalized with NGX_DONE. In particular, this fixes unwanted connection transition into the keepalive state after receiving EOF while discarding request body. With edge-triggered event methods that means the connection will last for extra seconds as set in the keepalive_timeout directive.