ERP5Type: fixed typo
erp5_test_result: use activeSense method of alarm instead of calling script

The activeSense method is doing more than calling the alarm script, it also change
the user. Without using activeSense, the alarm script will be called under the user
doing something on test node/ test suite, and this could conduct to different results
than if it is run with the nobody user.
erp5_test_result: run first test suite with no results

Optimize sorting of list of test suite to be executed by test nodes.
We give priority to test suite with older test results. This allows
to have test node resources in a more fair way.
ERP5Type: add get[Category]ShortTitle accessor

Short title is a property quite widely used, and it happens regularly
to display it in listbox. So such access is very convenient to have
by default.