Upgrade pre-cache to v8
Upgrade pre-cache to v8

agideon/heroku-buildpack-scala,Scalingo/scala-buildpack,heroku/heroku-buildpack-scala,Scalingo/scala-buildpack,yannickdeturck/heroku-buildpack-scala,heroku/heroku-buildpack-scala,agideon/heroku-buildpack-scala,yannickdeturck/heroku-buildpack-scala