bug 6158: move 'release tests' to xt/ directory; mirror long-running, net-tests and stress tests with xt/50_testname.t scripts to enforce their run before a release
bug 6158: move 'release tests' to xt/ directory; mirror long-running, net-tests and stress tests with xt/50_testname.t scripts to enforce their run before a release

git-svn-id: e9fe9b84e32fc5e57b7d09c40cd78b14ea28ed71@818439 13f79535-47bb-0310-9956-ffa450edef68

apache/spamassassin,apache/spamassassin,apache/spamassassin,apache/spamassassin,apache/spamassassin