Gantt methods

exec	Allows triggering Gantt actions
getReactiveState	Gets the state object with the reactive properties of Gantt
getState	Gets the state object that stores current values of most Gantt properties
getStores	Gets an object with the DataStore properties of Gantt
getTask	Gets an object with the task configuration
intercept	Allows intercepting and blocking/modifying actions
on	Allows attaching a handler to the inner events
setNext	Allows adding some action into the Event Bus order