This is required to support parallel test runs.
Among others, make thise files dynamic:
* test-spool
* rsyslog.input
* rsyslog.out*.log
* tmp.in
Also:
* convert presort test statement to function
* cleanup imfile truncation test
* cleanup imfile-growing-file-id test
some cruft was left due to copy and paste error
* serialize mysql tests
changes some of the test commands to use bash functions
includes some small bug fixes to tests where bugs were
previously not seen due to different plumbing.
