Does maven have pluggable available build extensions?

[Tony Lâmpada <to...@freedomsponsors.com>]

We all know maven has a lot of available
plugins<http://maven.apache.org/plugins/index.html>that do a lot of
useful stuff.

I recently learned about a different kind of extension point for maven
builds: build extensions<http://maven.apache.org/examples/maven-3-lifecycle-extensions.html>
.

Is there a similar list of useful build extensions that one can use?
And more specifically, one that can maybe help with
this<http://stackoverflow.com/questions/11749375/import-maven-plugin-configuration-by-composition-rather-than-inheritance-can-it>
?

Thanks
Tony