display-property-updates ignores properties defined in the parent POM

[ctubbsii]

One of the main reasons to use this plugin is to identify things that a user needs to override in their local POM to override what's being set in the parent. For example, the Apache parent POM specifies <surefire.version>3.1.0</surefire.version>. I don't currently have that set in my local POM, because 3.1.0 was the latest and I didn't need to override that. But now, 3.1.2 is out, and I should update it, to override the version specified in the parent POM.

It would be nice to have an option that would help users identify available updates so they can add versions in their own POM that they didn't have before, to override what's specified in the parent POM.

Conversely, it would be nice to identify version specifications that are redundant with the parent POM. If I specify 3.3.0, but the parent POM also has version 3.3.0, then it would be nice to have an option to remove my override, since it is no longer needed. This is a common situation when there's a bugfix to a plugin that you want to apply right away, but the parent POM hasn't provided a new release yet. So you temporarily override the version in the parent POM.