Change printColored to use timestampFormat.

text_formatter.go

diff --git a/text_formatter.go b/text_formatter.go
index 5f9ab46..17cc298 100644
--- a/text_formatter.go
+++ b/text_formatter.go
@@ -78,7 +78,7 @@
 		timestampFormat = DefaultTimestampFormat
 	}
 	if isColored {
-		f.printColored(b, entry, keys)
+		f.printColored(b, entry, keys, timestampFormat)
 	} else {
 		if !f.DisableTimestamp {
 			f.appendKeyValue(b, "time", entry.Time.Format(timestampFormat))
@@ -94,7 +94,7 @@
 	return b.Bytes(), nil
 }
 
-func (f *TextFormatter) printColored(b *bytes.Buffer, entry *Entry, keys []string) {
+func (f *TextFormatter) printColored(b *bytes.Buffer, entry *Entry, keys []string, timestampFormat string) {
 	var levelColor int
 	switch entry.Level {
 	case DebugLevel:
@@ -112,7 +112,7 @@
 	if !f.FullTimestamp {
 		fmt.Fprintf(b, "\x1b[%dm%s\x1b[0m[%04d] %-44s ", levelColor, levelText, miniTS(), entry.Message)
 	} else {
-		fmt.Fprintf(b, "\x1b[%dm%s\x1b[0m[%s] %-44s ", levelColor, levelText, entry.Time.Format(f.TimestampFormat), entry.Message)
+		fmt.Fprintf(b, "\x1b[%dm%s\x1b[0m[%s] %-44s ", levelColor, levelText, entry.Time.Format(timestampFormat), entry.Message)
 	}
 	for _, k := range keys {
 		v := entry.Data[k]