Feature/filestorage availabilityzones list (#153)

* sfs: Add support for Availability Zone List

* sfs: Add acceptance tests for Availability zones List

* sfs: Fix review comments
diff --git a/acceptance/openstack/sharedfilesystems/v2/availabilityzones_test.go b/acceptance/openstack/sharedfilesystems/v2/availabilityzones_test.go
new file mode 100644
index 0000000..8841160
--- /dev/null
+++ b/acceptance/openstack/sharedfilesystems/v2/availabilityzones_test.go
@@ -0,0 +1,29 @@
+package v2
+
+import (
+	"testing"
+
+	"github.com/gophercloud/gophercloud/acceptance/clients"
+	"github.com/gophercloud/gophercloud/openstack/sharedfilesystems/v2/availabilityzones"
+)
+
+func TestAvailabilityZonesList(t *testing.T) {
+	client, err := clients.NewSharedFileSystemV2Client()
+	if err != nil {
+		t.Fatalf("Unable to create shared file system client: %v", err)
+	}
+
+	allPages, err := availabilityzones.List(client).AllPages()
+	if err != nil {
+		t.Fatalf("Unable to list availability zones: %v", err)
+	}
+
+	zones, err := availabilityzones.ExtractAvailabilityZones(allPages)
+	if err != nil {
+		t.Fatalf("Unable to extract availability zones: %v", err)
+	}
+
+	if len(zones) == 0 {
+		t.Fatal("At least one availability zone was expected to be found")
+	}
+}