R1:d2baa88171fc

Allow Owners packages to have arbitrarily long names

Summary:
- Change column type from `sort128` to `sort`.
- Remove `originalName`. This column is unused. Long ago, we used it to generate a `Thread-Topic` header for mail, but just use PHIDs now (the value just needs to be stable for a given object, users normally don't see it).

Test Plan:
- Created a package with a beautifully long name. Magnificent!
- Grepped for `originalName` / `getOriginalName()`, found no Owners hits.
- Verified that…