Listing available algorithm providers in scheduler

List the available algorithm providers with 'kube-scheduler --help' under field `algorithm_provider`

plugin/pkg/scheduler/factory/plugins.go

@@ -19,6 +19,7 @@ package factory
 import (
 	"fmt"
 	"regexp"
+	"strings"
 	"sync"
 
 	algorithm "github.com/GoogleCloudPlatform/kubernetes/pkg/scheduler"
@@ -300,3 +301,12 @@ func validatePriorityOrDie(priority schedulerapi.PriorityPolicy) {
 		}
 	}
 }
+
+// ListAlgorithmProviders is called when listing all available algortihm providers in `kube-scheduler --help`
+func ListAlgorithmProviders() string {
+	var availableAlgorithmProviders []string
+	for name := range algorithmProviderMap {
+		availableAlgorithmProviders = append(availableAlgorithmProviders, name)
+	}
+	return strings.Join(availableAlgorithmProviders, " | ")
+}