Workaround for compilation failure and other Java versions

In case you are stuck with compilation/build errors you can try to use `ysoserial-all.jar` from the releases page in a docker container. (just a dirty workaround you possibly already knew) Use the recommended fix in #203 if you don't want to use docker.

Dockerfile
```Dockerfile
FROM openjdk:8-jdk-alpine
WORKDIR /app
COPY ./ysoserial-all.jar .
ENTRYPOINT ["java", "-jar", "ysoserial-all.jar"]
```

1. Build image
```
docker build -t ysoserial .
```

2. Run container
```
docker run --rm ysoserial [Command]
```

Workaround for #228