Remove Travis CI

It was replaced by a GitHub action, so replace the build status badge, too.

Signed-off-by: Stefan Weil <sw@weilnetz.de>

.zipignore

@@ -1,5 +1,4 @@
 .git
-.travis.yml
 .zipignore
 .gitignore
 example

README.md

@@ -1,7 +1,7 @@
 # ocr-fileformat
 
 [![Codacy Badge](https://api.codacy.com/project/badge/Grade/46847fb2bf764f77bd8feb35b003120a)](https://www.codacy.com/app/UB-Mannheim/ocr-fileformat?utm_source=github.com&utm_medium=referral&utm_content=UB-Mannheim/ocr-fileformat&utm_campaign=badger)
-[![Build Status](https://travis-ci.org/UB-Mannheim/ocr-fileformat.svg?branch=master)](https://travis-ci.org/UB-Mannheim/ocr-fileformat)
+[![Build Status](https://github.com/UB-Mannheim/ocr-fileformat/actions/workflows/ci.yml/badge.svg)](https://github.com/UB-Mannheim/ocr-fileformat/actions/workflows/ci.yml)
 [![GitHub release](https://img.shields.io/github/release/UB-Mannheim/ocr-fileformat.svg?maxAge=3600)](https://github.com/UB-Mannheim/ocr-fileformat/releases)
 [![ocr-fileformat Docker build](https://img.shields.io/docker/automated/ubma/ocr-fileformat.svg?maxAge=2592000?style=plastic)](https://hub.docker.com/r/ubma/ocr-fileformat)
 
@@ -258,4 +258,4 @@ During the installation process several projects are included (in [`./vendor`](.
 * [format-converters](https://github.com/OCR-D/format-converters) by OCR-D, [`Apache 2.0`](https://github.com/OCR-D/format-converters/blob/master/LICENSE)
 * [prima-page-converter](https://github.com/PRImA-Research-Lab/prima-page-converter/) by PRImA Research Lab , [`Apache 2.0`](https://github.com/PRImA-Research-Lab/prima-page-converter/blob/master/LICENSE)
 * [page-to-alto](https://github.com/kba/page-to-alto/) by Konstantin Baierer @kba, [`Apache 2.0`](https://github.com/OCR-D/format-converters/blob/master/LICENSE)
-* [textract2page](https://github.com/slub/textract2page/) by Arne Rümmler @rue-a, [`Apache 2.0`](https://github.com/OCR-D/format-converters/blob/master/LICENSE)
+* [textract2page](https://github.com/slub/textract2page/) by Arne Rümmler @rue-a, [`Apache 2.0`](https://github.com/OCR-D/format-converters/blob/master/LICENSE)