- move and update tests from testPayroll.py testNewPayroll.py

- add setSystemPreference method since we need a different one from testBPMCore (because of payroll specific preference property : preferred_payroll_resource_use_category_list)
- add some new categories and step to be able to have labour line in the model
- fix some mistakes like trade_phase path
- use stepTic


git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@27650 20353a03-c40f-0410-a6d1-a30d3c3de9de