Update setup.py.
Skip most tests that fail without buildbot_www.

The remaining tests that needlessly fail without buildbot_www are:
- buildbot.test.integration.test_master
- buildbot.test.unit.test_scripts_create_master.TestCreateMasterFunctions.test_createDB
- buildbot.test.unit.test_scripts_upgrade_master.TestUpgradeMasterFunctions.test_upgradeDatabase