[#71] update docs; -travis; +badge (#72)

README.md

@@ -4,16 +4,80 @@ This is the [wagon-maven-plugin](http://www.mojohaus.org/wagon-maven-plugin/).
 
 [![Maven Central](https://img.shields.io/maven-central/v/org.codehaus.mojo/wagon-maven-plugin.svg?label=Maven%20Central)](http://search.maven.org/#search%7Cga%7C1%7Cg%3A%22org.codehaus.mojo%22%20a%3A%wagon-maven-plugin%22)
 [![Apache License 2](https://img.shields.io/badge/wagon-Apache_v2-yellow.svg)](http://www.apache.org/licenses/LICENSE-2.0.txt)
-[![Build Status](https://travis-ci.org/mojohaus/wagon-maven-plugin.svg?branch=master)](https://travis-ci.org/mojohaus/wagon-maven-plugin)
+[![GitHub CI](https://github.com/mojohaus/wagon-maven-plugin/actions/workflows/maven.yml/badge.svg)](https://github.com/mojohaus/wagon-maven-plugin/actions/workflows/maven.yml)
+
+
+## Maintained versions
+
+Wagen Maven Plugin requires Maven 3.2.5+ and JDK 1.8+
+
+However, we maintain the latest Plugin version with the latest Maven.
+
+We execute tests against different operating systems and JDKs
+by [GitHub Actions](https://github.com/mojohaus/wagon-maven-plugin/actions/workflows/maven.yml?query=branch%3Amaster)
+
+## Contributing
+
+### Creating Issues
+
+If you find a problem please first search current opened and closed issues and pull requests.
+It can be that someone already has reported similar.
+
+You can also check current [milestone](https://github.com/mojohaus/wagon-maven-plugin/milestones)
+in order to see what will be in next release.
+
+Only when you can not find similar issue please create a new one in the
+[ticket system](https://github.com/mojohaus/wagon-maven-plugin/issues)
+and describe what is going wrong or what you expect to happen.
+
+If you have a full working example or a log file this is also helpful.
+
+You should of course describe only a single issue in a single ticket and not
+mixing up several things into a single issue.
+
+Please always check your issue with the latest Plugin and tha latest Maven version.
+
+### Creating a Pull Request
+
+Before you start working on more complicated change, new feature
+it is good practice to create an issue in
+the [ticket system](https://github.com/mojohaus/wagon-maven-plugin/issues)
+or send an emil to [development list](https://www.mojohaus.org/wagon-maven-plugin/mailing-lists.html)
+and describe what the problem is or what kind of feature you would like to add.
+Wait a few days for feedback from other contributors.
+Afterwards you can create an appropriate pull request.
+
+It is required if you want to get a pull request to be integrated into please
+squash your commits into a single commit which references the optional issue
+in the commit message which looks like this:
+
+```
+Fixed #Issue - change subject 
+
+a description
+```
+
+Please take consider that change subject will be used in release notes
+and will be present in git history so should be enough descriptive.
+
+This makes it simpler to merge it and this will also close the
+appropriate issue automatically in one go.
+This make the life as maintainer a little bit easier.
+
+A pull request has to fulfill only a single ticket and should never
+create/add/fix several issues in one, cause otherwise the history is hard to
+read and to understand and makes the maintenance of the issues and pull request
+hard or to be honest impossible.
 
 ## Releasing
 
-* Make sure `ssh-agent` is running.
-* Execute `mvn -B release:prepare release:perform`
+* Make sure `gpg-agent` is running.
+* Execute `./mvnw -B release:prepare release:perform`
 
 For publishing the site do the following:
 
 ```
 cd target/checkout
-mvn verify site scm-publish:publish-scm
+../mvnw site
+../mvnw scm-publish:publish-scm
 ```