modelVersion. This is required so that a change from modelVersion 4.0.0 to
  4.1.0 doesn't cause compatibility problems with users who have not upgraded
  their projects. It also allows for a certain amount of legacy support into the
  future. Therefore, we should rename this file from pom.xml in the maven-core
  jarfile to pom-4.0.0.xml (and successive revisions to the base pom made to

which might be interesting to read and for further discussion.

Getting Started
---------------

+ Make sure you have a [JIRA account](https://issues.apache.org/jira/).
+ Make sure you have a [GitHub account](https://github.com/signup/free).
+ If you're planning to implement a new feature, it makes sense to discuss your changes
  on the [dev list](https://maven.apache.org/mailing-lists.html) first.

- plugin in any default values
- check to see if anything is missing