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- constants - we hold here classes like AwesomePluginConstants.java and maybe some model enums that are plugin specific.
- hooks - model and view hooks like: ViewNameViewHooks.java, ModelNameHooks.java
- validators - model validators like: ModelNameValidators.java, SomeOtherModelNameValidators.java
- listeners - view listeners like: ViewNameViewHooksViewNameListeners.java
- workPlansColumnExtension - http://wiki.qcadoo.org/display/QCDMESDOC/WorkPlans+column+extension
...