Added mlp tutorial unit test
Used autopep8
Added skip_if_no_data
Ordered prompt numbers
Fixed string concatenation
Reverted test_autoencoded.py to its original form

To fix in another pull request
Updated mlp test unit
minor change to metadata
Put back original hyper-parameters in .ipynb file
skip_if_no_data() at the beginning of each test

Also autopep8
PEP 8
Merge pull request #593 from sebastien-j/master

Issue #371: mlp unit test