This may actually break binary compatibility and some sbt plugins.  E.g. I think sbt-idea may be using this.

You may need to manually deconstruct the case-class so that the unapply method still returns the same amount of values for consumers (yay).

The second alternative is to actually create a second case class "GlobalPuginData2" or something which has the original GlobalPluginData *and* the update report.  Then you can create a new key to store this new data, have the old key pull from the new key *AND* everything remains binary compatible.

Both are the gunky realities we live in in 0.13.x series :)