VCL: application proxy configuration

- Add support to configure VCL to set
  application proxy transport types
  and app_is_proxy flag via vcl
  config file or env vars.
- Clean up debug output.
- Rename session_scope -> app_scope.

Change-Id: I6e35f3cdd84daf0112133af8f33acd0152f87ca3
Signed-off-by: Dave Wallace <dwallacelf@gmail.com>
diff --git a/src/vcl/vppcom.h b/src/vcl/vppcom.h
index 85c06f1..a20ff14 100644
--- a/src/vcl/vppcom.h
+++ b/src/vcl/vppcom.h
@@ -23,14 +23,16 @@
 /*
  * VPPCOM Public API Definitions, Enums, and Data Structures
  */
-#define INVALID_SESSION_ID               (~0)
-#define VPPCOM_VRF_DEFAULT               0
-#define VPPCOM_CONF_DEFAULT              "/etc/vpp/vppcom.conf"
-#define VPPCOM_ENV_CONF                  "VCL_CONFIG"
-#define VPPCOM_ENV_APP_NAMESPACE_ID      "VCL_APP_NAMESPACE_ID"
-#define VPPCOM_ENV_APP_NAMESPACE_SECRET  "VCL_APP_NAMESPACE_SECRET"
-#define VPPCOM_ENV_SESSION_SCOPE_LOCAL   "VCL_SESSION_SCOPE_LOCAL"
-#define VPPCOM_ENV_SESSION_SCOPE_GLOBAL  "VCL_SESSION_SCOPE_GLOBAL"
+#define INVALID_SESSION_ID                   (~0)
+#define VPPCOM_VRF_DEFAULT                   0
+#define VPPCOM_CONF_DEFAULT                  "/etc/vpp/vcl.conf"
+#define VPPCOM_ENV_CONF                      "VCL_CONFIG"
+#define VPPCOM_ENV_APP_PROXY_TRANSPORT_TCP   "VCL_APP_PROXY_TRANSPORT_TCP"
+#define VPPCOM_ENV_APP_PROXY_TRANSPORT_UDP   "VCL_APP_PROXY_TRANSPORT_UDP"
+#define VPPCOM_ENV_APP_NAMESPACE_ID          "VCL_APP_NAMESPACE_ID"
+#define VPPCOM_ENV_APP_NAMESPACE_SECRET      "VCL_APP_NAMESPACE_SECRET"
+#define VPPCOM_ENV_APP_SCOPE_LOCAL           "VCL_APP_SCOPE_LOCAL"
+#define VPPCOM_ENV_APP_SCOPE_GLOBAL          "VCL_APP_SCOPE_GLOBAL"
 
 typedef enum
 {