Extract portforward to separate package (#728)

* Extract port-forward from CLI to own package (for reuseability)
* Extract CLI logging to subpackage

fission/upgrade.go

@@ -16,6 +16,7 @@ import (
 
 	"github.com/fission/fission"
 	"github.com/fission/fission/crd"
+	"github.com/fission/fission/fission/log"
 	"github.com/fission/fission/v1"
 )
 
@@ -37,7 +38,7 @@ type (
 
 func getV1URL(serverUrl string) string {
 	if len(serverUrl) == 0 {
-		fatal("Need --server or FISSION_URL set to your fission server.")
+		log.Fatal("Need --server or FISSION_URL set to your fission server.")
 	}
 	isHTTPS := strings.Index(serverUrl, "https://") == 0
 	isHTTP := strings.Index(serverUrl, "http://") == 0
@@ -57,7 +58,7 @@ func get(url string) []byte {
 	checkErr(err, "reading server response")
 
 	if resp.StatusCode != 200 {
-		fatal(fmt.Sprintf("Failed to fetch fission v0.1 state: %v", string(body)))
+		log.Fatal(fmt.Sprintf("Failed to fetch fission v0.1 state: %v", string(body)))
 	}
 	return body
 }
@@ -251,7 +252,7 @@ func upgradeDumpState(c *cli.Context) error {
 	checkErr(err, "reach fission server")
 	if resp.StatusCode == http.StatusNotFound {
 		msg := fmt.Sprintf("Server %v isn't a v1 Fission server. Use --server to point at a pre-0.2.x Fission server.", u)
-		fatal(msg)
+		log.Fatal(msg)
 	}
 
 	upgradeDumpV1State(u, filename)