GSoC 2014: Standard Extreme Learning Machines

Finished implementing the standard extreme learning machines (ELMs). I am getting the following results with 550 hidden neurons against the digits datasets,

Training accuracy using the logistic activation function: 0.999444
Training accuracy using the tanh activation function: 1.000000

Fortunately, this algorithm is much easier to implement and debug than multi-layer perceptron :).
I will push a test file soon.

@ogrisel , @larsmans
also please put parens around the subclauses of this condition. I am not sure this condition is actually working as expected: https://docs.python.org/3/reference/expressions.html#operator-precedence 

Better be explicit with parens in when conditions mix both `or` and `and` operators in the same expression.