buildFederatedSchema ignores custom directives

[padenj]

Apollo's buildFederatedSchema only adds built-in directives to the schema. It does not honor the schemaDirectives option. Therefore, any custom directives are ignored. See issue apollographql/apollo-feature-requests#145.

A workaround could be to use mergeSchemas to add in the schema definition after building the federated schema.

[tlivings]

Fixed in #40

[padenj]

The fix for this issue causes extended properties to be ignored when publishing a schema to Apollo GraphManager. PR #41 is a less intrusive way to add custom directives with less side effects on the federated schema.