Remove -sourcepath from the options of library/console
Remove -sourcepath from the options of library/console

Before this change, library/{console, consoleQuick} REPL startup and
maybe each REPL line evaluation was typechecking src/library rather
than using the class files.

I never noticed this before because it isn't a common task to run,
I only tried it as part of some ad-hoc testing of the build in
our effort to upgrade to SBT 1.x.

lrytz/scala,lrytz/scala,lrytz/scala,scala/scala,martijnhoekstra/scala,scala/scala,lrytz/scala,scala/scala,lrytz/scala,lrytz/scala,scala/scala,martijnhoekstra/scala,martijnhoekstra/scala,scala/scala,martijnhoekstra/scala,martijnhoekstra/scala,scala/scala,martijnhoekstra/scala