feat(libhelm) import libhelm into CE pkg directory [EE-4650] (#8138)

* import libhelm and update some paths

* remove file

* update readme

pkg/libhelm/time/time_test.go

@@ -0,0 +1,83 @@
+/*
+Copyright The Helm Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package time
+
+import (
+	"encoding/json"
+	"testing"
+	"time"
+)
+
+var (
+	testingTime, _    = Parse(time.RFC3339, "1977-09-02T22:04:05Z")
+	testingTimeString = `"1977-09-02T22:04:05Z"`
+)
+
+func TestNonZeroValueMarshal(t *testing.T) {
+	res, err := json.Marshal(testingTime)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if testingTimeString != string(res) {
+		t.Errorf("expected a marshaled value of %s, got %s", testingTimeString, res)
+	}
+}
+
+func TestZeroValueMarshal(t *testing.T) {
+	res, err := json.Marshal(Time{})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if string(res) != emptyString {
+		t.Errorf("expected zero value to marshal to empty string, got %s", res)
+	}
+}
+
+func TestNonZeroValueUnmarshal(t *testing.T) {
+	var myTime Time
+	err := json.Unmarshal([]byte(testingTimeString), &myTime)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !myTime.Equal(testingTime) {
+		t.Errorf("expected time to be equal to %v, got %v", testingTime, myTime)
+	}
+}
+
+func TestEmptyStringUnmarshal(t *testing.T) {
+	var myTime Time
+	err := json.Unmarshal([]byte(emptyString), &myTime)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !myTime.IsZero() {
+		t.Errorf("expected time to be equal to zero value, got %v", myTime)
+	}
+}
+
+func TestZeroValueUnmarshal(t *testing.T) {
+	// This test ensures that we can unmarshal any time value that was output
+	// with the current go default value of "0001-01-01T00:00:00Z"
+	var myTime Time
+	err := json.Unmarshal([]byte(`"0001-01-01T00:00:00Z"`), &myTime)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !myTime.IsZero() {
+		t.Errorf("expected time to be equal to zero value, got %v", myTime)
+	}
+}