Hotfix/realtime revision history bug

[OGProgrammer]

I added the revision history realtime plugin and encountered a bug where a collaborator that connects runs into this edge case where this.value is null and initialData is undefined which results in an attempt to call setData with null even though data was already set previously.

[OGProgrammer]

Please squash this when merging since I had that last request to add error event. Which btw I still suggest you add that. None of the recommendations mentioned worked.