Disabled xunit support in vdsm_master_unit-tests_merged

Hi infra, I disable nose xunit support in this job: http://jenkins.ovirt.org/job/vdsm_master_unit-tests_merged/ The xunit plugin trigger a segfault in Python during tests, which cause most runs to fail. Changes: 1. disable xunit plugin: # xunit cause segfault in python - disabled until it is fixed. # export NOSE_WITH_XUNIT=1 2. Remove the post job collection of nosetests.xml Thanks, Nir