chore: bring back unused util.go file as removing it is a breaking change

Author: leonklingele

util.go

@@ -3,8 +3,43 @@ package migrate
 import (
 	"fmt"
 	nurl "net/url"
+	"strings"
 )
 
+// TODO: This file is not in use anymore inside this project.
+// Remove it in the v5 release.
+
+// MultiError holds multiple errors.
+//
+// Deprecated: Use github.com/hashicorp/go-multierror instead
+type MultiError struct {
+	Errs []error
+}
+
+// NewMultiError returns an error type holding multiple errors.
+//
+// Deprecated: Use github.com/hashicorp/go-multierror instead
+func NewMultiError(errs ...error) MultiError {
+	compactErrs := make([]error, 0)
+	for _, e := range errs {
+		if e != nil {
+			compactErrs = append(compactErrs, e)
+		}
+	}
+	return MultiError{compactErrs}
+}
+
+// Error implements error. Multiple errors are concatenated with 'and's.
+func (m MultiError) Error() string {
+	var strs = make([]string, 0)
+	for _, e := range m.Errs {
+		if len(e.Error()) > 0 {
+			strs = append(strs, e.Error())
+		}
+	}
+	return strings.Join(strs, " and ")
+}
+
 // suint safely converts int to uint
 // see https://goo.gl/wEcqof
 // see https://goo.gl/pai7Dr