add a comment on s3 methods re-instalation to ess-developer.R

git-svn-id: https://svn.r-project.org/ESS/trunk@5406 0bbaf3bd-34e0-0310-bf65-c717079852d4
activate ess-tracebug by default

git-svn-id: https://svn.r-project.org/ESS/trunk@5407 0bbaf3bd-34e0-0310-bf65-c717079852d4