Feature/trigger in dataextensions

[tiller1010]

Description

Allows StaticPublishingTrigger to be added in DataExtensions

Manual testing steps

• Add a DataExtension to a DataObject without StaticPublishingTrigger
• Also add the SiteTreePublishingEngine extension to that DataObject
• Confirm the instances of the DataObject have their URLs queued to be cached when saved/published

Issues

Closes #211

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