Simplify and robustify test about dependency cycles
Simplify (?) and robustify tests about exceptions handling
pep8
Simplify and robustify tests for mutlipe executions
Simplify tests about single-threaded execution
Add missing tearDowns
Simplify test for multi-threaded execution
Test str(CompoundException)
Test Action.status before execution
Remove useless properties
Replace a set of exclusive booleans by a single enum
Time all actions
Let's implement Action.getPreview()
Preview dependencies
Do not repeat actions in preview
Preview: allow duplicated labels, not duplicated actions
Acknowledge that getPreview is not deterministic
Use a set instead of a list to avoid duplication in getPreview