tls: enforce certificate verification

- add option to use test certificate in the ca chain
- add hostname to extended session endpoint fields and connect api
  parameters. If hostname is present, certificate validation is
  enforced.
- use /etc/ssl/certs/ca-certificates.crt to bootstrap CA cert. A
  different path can be provided via startup config

Change-Id: I046f9c6ff3ae6a9c2d71220cb62eca8f7b10e5fb
Signed-off-by: Florin Coras <fcoras@cisco.com>
diff --git a/src/vnet/session/application_interface.h b/src/vnet/session/application_interface.h
index 2ab09d6..deddb64 100644
--- a/src/vnet/session/application_interface.h
+++ b/src/vnet/session/application_interface.h
@@ -83,13 +83,11 @@
   union
   {
     char *uri;
-    session_endpoint_t sep;
+    session_endpoint_extended_t sep;
   };
   u32 app_index;
   u32 api_context;
 
-  /* Used for redirects */
-  void *mp;
   session_handle_t session_handle;
 } vnet_connect_args_t;