Summary:
Handlers were added in an intermediate form of tbv2 but those intermediate
forms have now been removed. Remove all the handlers to make grepping/find and
replaces easier across the types.
Test Plan:
- CI
This change is fully backwards compatible with the old ContainerInfo
parser, as it is just adding new fields.
The old fields will continue to be used by legacy OICodeGen until that
is removed.
Also add a README to document the format.
