Including parent projects does not look useful -> false by default
Add prerequisites
Add versions to reporting plugins to avoid build warnings
Doc
Rename DependencyGraphByGroupIdMojo ->
AggregatingDependencyGraphByGroupIdMojo.java (part 1)
Rename DependencyGraphByGroupIdMojo ->
AggregatingDependencyGraphByGroupIdMojo.java (part 2)
Change mojo name to aggregate-by-groupid