auto-update JenkinsConfiguration working copy in home directory, so valgrind suppressions are always up-to-date

moved valgrind suppressions out of the docker images and use them from the msk_jenkins home directory

do not run valgrind with trace children, as it leads to strange errors. if needed, we should add this as an option

- fix access rights of /scratch

- build projects only for labels which have been built for all dependencies