Refs #4873 - Add bundle command_execution_module() and adapt command_execution() and its tests

Refs #4873 - Add bundle command_execution_module() and adapt command_execution() and its tests

cf http://www.rudder-project.org/redmine/issues/4873
with this approach, you'll always have repaired status
You should have a convention in the output of the modules, to define when you have a repaired and when you have a kept
Idealy, if the module changes something, then it is repaired, else it is kept (or you can also fail if it fails)