Major Description
When generating the client api library for go the default containerizer used as a hack for AURORA-1185 breaks and causes the client lib to not be generated correctly. The default value for the optional field `container = { "mesos": {} }` is not necessary as it is defaulted in java code on the api side.
Tracking this down it looks like the default value was a last minute addition based on some review comments and is not necessary or used anywhere. Removing the default value does not impact anything.