Metadata does not return with batch_iter even if include_metadata=True

[MishaLaskin]

dat = minerl.data.make('MineRLTreechopVectorObf-v0')
for struct in tqdm(dat.batch_iter(batch_size=16, seq_len=32, 
                                  num_epochs=1, preload_buffer_size=32,
                                  include_metadata=True)):
    print(struct)

struct outputs without any metadata in this example

[Miffyli]

Hey. I can take look at this tomorrow. Probably a silly logic typo somewhere in the PR.

Related PR #495

[Miffyli]

After bit of digging I realized I did not actually push all changes I made to #495 (I felt like I missed something). I will be continuing tomorrow on a fix for this. Thanks for pointing this out!

[Miffyli]

I removed include_metadata keyword for batch_iter as proper support for it proved to be very tricky to implement. I recommend using load_data if you wish to get the metadata info as well.

For future, see fix/batch_iter_2 for WIP progress.