Only 'MineRLObtainDiamond-v0' is allowed durring training

[brandonhoughton]

Currently the train_locally.sh prevents participants from using any other environment via the
check_for_allowed_environment(self, environment, payload): call. For training we should allow participants to use all environments in Minerl

[kaixin96]

Have you fixed this? I still can't use other env during training (e.g. treechop). The deadline of round 1 is approaching !!