Default on startup to applying all updates before triggering subscriptions

[KyleAMathews]

Right now if you visit an app that's had a lot of updates, you see a long series of fast re-renders while changes stream in.

This is slow and undesirable. Instead there should just be a batch update once all updates have arrived and then trigger just one re-render.

[balegas]

This might be one of the oldest things in our todo list :D.

• We need to have some additional sync state info to know that we're catching up with the server
• Batching updates would speedup the process a lot

[KyleAMathews]

Haha I'll bet!