Various fixes so tests pass reliably under ruby 1.8.7 and 1.9.3 plus enhancements

Tests pass for both ruby 1.8.7 and 1.9.3 - (1.8.7 tested on private cruisecontrol server, both tested on https://travis-ci.org/ianheggie/cruisecontrol.rb - interesting the reported number of tests is lower under cruise (default build) than under travis (runs rake) )

Includes jshraibman-mdsol's pull request (/ on end of artifacts directories)

Artifacts and changesets are listed in sorted order (as hash doesn't list keys in a reliable order and thus sometimes tests failed depending on what else had happened beforehand)

Note - for some reason the number of tests reported when testing cruisecontrolrb under cruisecontrolrb is less than when manually run or under travis (ruby 1.8.7):

under cruisecontrolrb:

265 tests, 655 assertions, 0 failures, 0 errors
64 tests, 213 assertions, 0 failures, 0 errors
22 tests, 42 assertions, 0 failures, 0 errors

under travis / manual ( just running "rake" ):

401 tests, 967 assertions, 0 failures, 0 errors
64 tests, 213 assertions, 0 failures, 0 errors
22 tests, 42 assertions, 0 failures, 0 errors

and that it runs more assertions under ruby 1.9.3

401 tests, 1012 assertions, 0 failures, 0 errors, 0 skips
64 tests, 216 assertions, 0 failures, 0 errors, 0 skips
22 tests, 45 assertions, 0 failures, 0 errors, 0 skips