New Data Set persistence and endpoints

This is a breaking change for Data Sets that are under BETA FF

Anybody who created data sets before this epic will not be able to see them in Data Set Manager anymore.
Data Set fragment configuration will no longer display previous data sets as options.
Data Set fragment placed on a page will no longer show anything.
The Data Set Views have been removed. From now on a Data Set has only a view.
New Data Set endpoints are available and working under datas-et-admin (ex: http://localhost:8080/o/api?endpoint=http://localhost:8080/o/data-set-admin/data-sets/openapi.json)
All Data Set endpoints are still available and working under data-set-manager but not used by the Data Set Manager or Frontend Data Set. Information from created Data Sets before this change is stored in them (ex: http://localhost:8080/o/api?endpoint=http://localhost:8080/o/data-set-manager/data-sets/openapi.json)

More Info: LPD-29979