Create a release plugin

[yannick-roeder]

The plugin should apply and configure the following plugins:

• net.researchgate.release
• org.hildan.github.changelog

Addtionally it should allow disabling push to remote through a property disablePushToRemote when releasing:

project.extensions.disablePushToRemote = project.hasProperty("disablePushToRemote") ? project.disablePushToRemote : false
project.release {
    git {
        pushToRemote.set(project.disablePushToRemote.toBoolean() ? false : "origin")
    }
}

[philipp94831]

I think we don't use the changelog plugin anymore but the release plugin would still be much appreciated