[DCOS-38519] fix flakiness in test_zzzrecovery.test_shutdown_host_teardown (#2560)
[DCOS-38519] fix flakiness in test_zzzrecovery.test_shutdown_host_teardown (#2560)

Increasing the count of world pods to minimize risk of tasks on shut down host. Adding install/uninstall helper with options as well for the tests
mesosphere/dcos-commons,mesosphere/dcos-commons,mesosphere/dcos-commons,mesosphere/dcos-commons,mesosphere/dcos-commons