Upgraded contribution guide lines

Added ReleaseNotes.md

README.md

@@ -54,3 +54,42 @@ For publishing the site do the following:
 cd target/checkout
 mvn verify site site:stage scm-publish:publish-scm
 ```
+
+## Contribution
+
+### Creating Issues
+
+If you find a problem please create an 
+[issue in the ticket](https://github.com/mojohaus/versions-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 different things into a single issue.
+
+### Creating a Pull Request
+
+Before you create a pull request it is necessary to create an issue in
+the [ticket system](https://github.com/mojohaus/versions-maven-plugin/issues)
+and describe what the problem is or what kind of feature you would like
+to add. 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 issue in the
+commit message which looks like this:
+
+```
+Fixed #Issue
+ o Description.
+```
+
+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.
+
+Furthermore it is necessary to create appropriate entries into the `ReleaseNotes.md`
+file as well.

ReleaseNotes.md

@@ -0,0 +1,53 @@
+# Release Notes
+
+## 2.5 (NOT YET RELEASED)
+
+ * [Fixed Issue 166][issue-166]
+
+   Upgraded modello-maven-plugin to 1.9.1
+
+ * [Fixed Issue 167][issue-167]
+
+   Upgraded versions-maven-plugin from 2.1 to 2.4
+
+ * [Fixed Issue 168][issue-168]
+
+   Added allowMajorUpdates, allowMinorUpdates, allowIncrementalUpdates
+   to resolve-ranges and display-property-updates goal.
+
+ * [Fixed Issue 37][issue-37]
+
+   Enhanced documentation for aggegator modules.
+
+ * [Fixed Issue 46][issue-46]
+
+   Added processDependencyManagement option to control the reporting
+   of dependencyManagement.
+   Thanks to Bruce Brouwer.
+
+ * [Fixed Issue 94][issue-94]
+
+   introduced allowMajorUpdates, allowMinorUpdates,
+   allowIncrementalUpdates.
+   introduced allowAnyUpdates for compatibility which
+   will be removed in 3.0.0 of the plugin.
+
+ * [Fixed Issue 34][issue-34]
+
+   Added implementation to report the plugin dependencies as well.
+   Added IT's for reporting updates about dependencies in plugins,
+   plugins defined in pluginManagement.
+
+* [Fixed Issue 162][issue-162]
+
+  Upgraded cobertura-maven-plugin used in report section
+  to 2.7.
+
+[issue-34]: https://github.com/jenkinsci/java-client-api/issues/34
+[issue-37]: https://github.com/jenkinsci/java-client-api/issues/37
+[issue-46]: https://github.com/jenkinsci/java-client-api/issues/46
+[issue-94]: https://github.com/jenkinsci/java-client-api/issues/94
+[issue-162]: https://github.com/jenkinsci/java-client-api/issues/162
+[issue-166]: https://github.com/jenkinsci/java-client-api/issues/166
+[issue-167]: https://github.com/jenkinsci/java-client-api/issues/167
+[issue-168]: https://github.com/jenkinsci/java-client-api/issues/168