failover unit test improvements

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=slony1-engine.git;a=commitdiff;h=1585f5a793980ed3150d1cbfe20c0d23aa870ad3

Modified Files
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clustertest/disorder/tests/BasicTest.js            | 29 ++++++++++++++-
clustertest/disorder/tests/FailNodeTest.js         |  1 -
.../disorder/tests/MultinodeCascadeFailover.js     | 43 ++++++++++++++++++----
clustertest/disorder/tests/MultinodeFailover.js    | 13 +++----
4 files changed, 69 insertions(+), 17 deletions(-)