Add basic backwards compatible support for bragg 2 in bragg 1

[SamVerschueren]

In order to upgrade from bragg 1 to bragg 2, it would be nice if bragg 1 understood requests from [email protected] for instance. That way interaction between multiple Lambda functions is more loosely coupled and version mismatches should still work. A lambda function running bragg 2 could invoke bragg 1. And maybe we should add support for bragg 1 calls to bragg 2 as well to make it even more simple.