* origin/topic/robin/conn-ids:
Moving uid from conn_id to connection, and making output determistic if a hash seed is given.
Extending conn_id with a globally unique identifiers.
Removing everything related to trace rewriting.
(I wasn't too careful in ensuring that I catch everything in the
scripts; Seth is working on those anyway.)
(Merging by cherry-picking the corresponding commit, as the branch was
accidentally made off of the logging stuff).
