tcp: improve builtin http server

Additionally:
- remove opaques from stream_session_t
- ensure first segment manager is only used once per app.

Change-Id: I143d1fdb8effc88815ef969b78122ba3ac29e06e
Signed-off-by: Florin Coras <fcoras@cisco.com>
diff --git a/src/vnet/tcp/builtin_server.c b/src/vnet/tcp/builtin_server.c
index 295c189..80a9556 100644
--- a/src/vnet/tcp/builtin_server.c
+++ b/src/vnet/tcp/builtin_server.c
@@ -267,7 +267,7 @@
   shmem_hdr = am->shmem_hdr;
   bsm->vl_input_queue = shmem_hdr->vl_input_queue;
   bsm->my_client_index =
-    vl_api_memclnt_create_internal ("tcp_test_server", bsm->vl_input_queue);
+    vl_api_memclnt_create_internal ("http_test_server", bsm->vl_input_queue);
   return 0;
 }