Enhancement: Goal to update plugin versions.

[Mavelous]

I can use versions:display-plugin-updates to see which plugins can be updated. However, there's no goal to actually edit the pom.xml file to enact those changes.

There's a goal to do this for dependencies: versions:use-latest-releases or versions:use-next-releases.
I can do the same for dependency versions that I've extracted to properties: versions:update-properties.
But I can't automatically do that for plugin versions.