Simulation train method breaks if there are any other zip files in the directory

[SaharEs]

When there are any other zip files in the directory, when simulation.train() is called, seems like it falls in an endless loop and creates many training.zip files within themselves and ends up exploding in size.

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[slinlee]

#44 will delete the training.zip file after uploading, unless the user enables debug_mode.

[slinlee]

@SaharEs pointed out the key part of this bug is if there is an existing zip file in the dir, such as 'Trained Poilcy.zip' above