instead of trashing editing file in cli, write err msg and re-edit

cmd/pttodo-cli/cli.go

@@ -146,6 +146,20 @@ func edit(dry bool, filepath string) error {
 		return nil
 	}
 	verify := func() error {
+		for {
+			err := verifyFile(tempFile)
+			if err == nil {
+				break
+			}
+			log.Printf("%v, press <Enter> to resume editing", err)
+			b := make([]byte, 1)
+			if _, err := os.Stdin.Read(b); err != nil {
+				break
+			}
+			if err := vi(); err != nil {
+				return err
+			}
+		}
 		return verifyFile(tempFile)
 	}
 	save := func() error {