ClusterManager: Implements support of remote clusters.

After this change users will be able to:
* Create cluster and add/remove servers to it
* Install apps on remote cluster
* Move already installed apps between clusters
* Apps running on server being removed will auto-migrate
  to another server from that same cluster

This is achieved by:
* Installing and running minimal version of dodo on remote cluster
* Ingress-nginx is installed automatically on new clusters
* Next to nginx we run VPN client in the same pod, so that
  default cluster can establish secure communication with it
* Multiple reverse proxies are configured to get to the
  remote cluster service from ingress installed on default cluster.

Next steps:
* Support remote clusters in dodo apps (prototype ready)
* Clean up old cluster when moving app to the new one. Currently
  old cluster keeps running app pods even though no ingress can
  reach it anymore.

Change-Id: Iffc908c93416d4126a8e1c2832eae7b659cb8044
diff --git a/core/installer/cmd/rewrite.go b/core/installer/cmd/rewrite.go
index 3e2961b..0f018e4 100644
--- a/core/installer/cmd/rewrite.go
+++ b/core/installer/cmd/rewrite.go
@@ -1,7 +1,6 @@
 package main
 
 import (
-	"fmt"
 	"log"
 	"os"
 
@@ -62,16 +61,7 @@
 	log.Println("Creating repository")
 	r := installer.NewInMemoryAppRepository(installer.CreateAllApps())
 	hf := installer.NewGitHelmFetcher()
-	mgr, err := installer.NewAppManager(repoIO, nil, nil, hf, nil, "/apps")
-	if err != nil {
-		return err
-	}
-	env, err := mgr.Config()
-	if err != nil {
-		return err
-	}
-	fmt.Printf("%+v\n", env)
-	log.Println("Read config")
+	mgr, err := installer.NewAppManager(repoIO, nil, nil, hf, nil, nil, "/apps")
 	if err != nil {
 		return err
 	}