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
Hi @agramfort , isn't this technically ridge regression? I am minimizing the L2 norm of the coefficients  in the objective function - like in the equation below. Thanks.

![l_elm](https://cloud.githubusercontent.com/assets/3382128/3462463/bc2011e8-022d-11e4-8061-42cbf95116c1.PNG)