[eclipse-plugin][2.8] Scala builder and manual changes to project structure

Hello,

Current scala builder has problems when preexisting artifacts such as:
class files, classes, objects etc get removed or renamed. Basically it
starts throwing out errors about "such and such artifact is not found"
on the next attempt to build. Cleaning the project and then rebuilding
makes the errors go away.

It would be nice if upon discovery that it can no longer find some
artifact scala builder would automatically do an equivalent of cleaning
the project and perfoming a full rebuild. Would save a lot of clicking
around.

Linas.