Clean up pack targets. Better dependency tracking.
Clean up pack targets. Better dependency tracking.

Target pack.@{project} is considered up to date iff
classes emitted by quick.@{project} are.

TODO: 318dbca0706287a3680c5b040506d47cb7e7e33a@{project}".
For now, they are duplicated as references
to `${build-@{stage}.dir}/classes/@{destproject}`
(in staged-scalac and *.build.path)

martijnhoekstra/scala,lrytz/scala,jvican/scala,shimib/scala,martijnhoekstra/scala,lrytz/scala,felixmulder/scala,felixmulder/scala,scala/scala,shimib/scala,scala/scala,scala/scala,shimib/scala,lrytz/scala,jvican/scala,shimib/scala,lrytz/scala,martijnhoekstra/scala,martijnhoekstra/scala,jvican/scala,scala/scala,slothspot/scala,scala/scala,felixmulder/scala,felixmulder/scala,slothspot/scala,slothspot/scala,jvican/scala,lrytz/scala,felixmulder/scala,jvican/scala,slothspot/scala,slothspot/scala,jvican/scala,martijnhoekstra/scala,slothspot/scala,shimib/scala,jvican/scala,felixmulder/scala,scala/scala,felixmulder/scala,lrytz/scala,martijnhoekstra/scala,slothspot/scala,shimib/scala