AppManager: Support exposing ports on public networks

Sets up [public ingress -> private ingress -> remote cluster] proxy chain

Change-Id: I6376a006b2692c31f3cb895bbfd6e373182e8824
diff --git a/core/installer/app.go b/core/installer/app.go
index e57fee8..9c658df 100644
--- a/core/installer/app.go
+++ b/core/installer/app.go
@@ -102,8 +102,9 @@
 	Protocol    string `json:"protocol"`
 	Port        int    `json:"port"`
 	Service     struct {
-		Name string `json:"name"`
-		Port int    `json:"port"`
+		Name      string `json:"name"`
+		Namespace string `json:"namespace,omitempty"`
+		Port      int    `json:"port"`
 	} `json:"service"`
 }