Support table mutation operations in Mimir

[okennedy]

Current behavior: INSERT, UPDATE, DELETE, and ALTER TABLE are not supported.

Desired behavior: These operations are supported.

As per the discussion in #321, the most straightforward way to do this would be through re-enactment (supplanting the corresponding operations in Vizier, as proposed in #349).

(This task was originally from #321, but was split out due to being out-of-scope.)