R1:741fb747db42

Implement "replace" transactions in Pholio without "applyInitialEffects"

Summary:
Depends on D19923. Ref T11351. Currently, this transaction takes an `Image` as the `newValue` and uses some magic to reduce it into PHIDs by the time we're done.

This creates some problems today where I'd like to get rid of `applyInitialEffects` for MFA code. In the future, it creates a problem becuase there's no way to pass an entire `Image` object over the API.

Instead, create the `Image` first, then just provide the…