Summary:
Also add the ability to mark an argument as required.
Added a string constant `OpSchema::Arg_IsTest` for `is_test` arg.
If users define the `is_test` argument with `ArgIsTest(...)`, then it automatically becomes required argument, in the meanwhile user can still use `Arg("is_test", ...)` to define an optional `is_test` argument.
Reviewed By: akyrola
Differential Revision: D5812391
fbshipit-source-id: eaaba50d027813a8012389edc6c459de23c3c728
Summary: generates a fair amount of documentation from the operators. also provides a framework for later documentation generation and custom syntax.
Reviewed By: dzhulgakov
Differential Revision: D4168311
fbshipit-source-id: 89ae9d023ad883623cdc1879c11e10b202b68793
