Fix go lint error and add golint checks to a pre-commit hook

pkg/internal/error/kustomizationerror.go

@@ -20,7 +20,7 @@ import (
 	"fmt"
 )
 
-// First pass to encapsulate fields for more informative error messages.
+// KustomizationError represents an error with a kustomization.
 type KustomizationError struct {
 	KustomizationPath string
 	ErrorMsg          string
@@ -30,6 +30,7 @@ func (ke KustomizationError) Error() string {
 	return fmt.Sprintf("Kustomization File [%s]: %s\n", ke.KustomizationPath, ke.ErrorMsg)
 }
 
+// KustomizationErrors collects all errors.
 type KustomizationErrors struct {
 	kErrors []error
 }
@@ -42,14 +43,17 @@ func (ke *KustomizationErrors) Error() string {
 	return errormsg
 }
 
+// Append adds error to a collection of errors.
 func (ke *KustomizationErrors) Append(e error) {
 	ke.kErrors = append(ke.kErrors, e)
 }
 
+// Get returns all collected errors.
 func (ke *KustomizationErrors) Get() []error {
 	return ke.kErrors
 }
 
+// BatchAppend adds all errors from another KustomizationErrors
 func (ke *KustomizationErrors) BatchAppend(e KustomizationErrors) {
 	for _, err := range e.Get() {
 		ke.kErrors = append(ke.kErrors, err)