project: Add the aspect_ratio dynamic property
timeline: Avoid calling a callback method directly
timeline: Get rid of method used in a single place
timeline: Test directly the element, not its parent
timeline: Be more strict when a timeline element is added
tests: Allow the tests to be run by frameworks like nosetests
tests: Activate test_log
tests: Simplify the no color logging setting
loggable: Make sure funcname is always set
loggable: Pass the correct file path when calling handler
loggable: Reuse the code calling the handlers
loggable: Fix the getFileLine return value when there is an error
tests: Update test_log
tests: Update the ProjectManager unittests

Also moved them to test_project.py so they can be found easily since the
ProjectManager class is in project.py.