- code cleaning

Otherwise it will run all tests in all dirs it finds

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

remove echo() and refactoring to reduce the number of steps - this should make the logs easier to read

- improved some comments