List all the metadata returned by neural networks benchmarks

[Deathn0t]

The list of metadata returned by all benchmarks tuning neural networks should be listed a current list is:

• num_parameters: integer value of the number of trainable parameters of the neural network.
• budget: scalar value (float/int) of the budget consumed by the neural network. Therefore the budget should be defined for each benchmark (e.g., number of epochs in general).
• stopped: boolean value indicating if the evaluation was stopped before consuming the maximum budget.
• train_X: scalar value of the training metrics (replace X by the metric name, 1 key per metric).
• valid_X: scalar value of the validation metrics (replace X by the metric name, 1 key per metric).
• test_X: scalar value of the testing metrics (replace X by the metric name, 1 key per metric).

Also add the @profile decorator to all functions.

[Deathn0t]

Added to the README in https://github.com/deephyper/benchmark/commit/1d2c7211bcff5ecb29b1710c68b844bb7ed1144d