Enhancement: Allow configuration using system properties

[domkun]

As I am using the plugin in a GitLab CI/CD component it is sometimes useful to execute the plugin without any changes to the pom.xml.

The possibility to configure the plugin using system properties would be great to have.

[chkal]

Fixed via #6. Thanks a lot for your help. I'll try to find some time over the weekend to publish a new release!

[chkal]

I just released version 1.1.0 to Maven Central. It may take a few hours for the release to show up there.

Thanks again for your help!

[domkun]

Thanks a lot for your effort. Glad I could Help.