[mlpack] Removing the ToString() methods from mlpack classes

[Ryan Curtin]

Hello there,

I've just opened a pull request intending to remove the ToString()
functions included with most mlpack classes:

https://github.com/mlpack/mlpack/pull/487

I wanted to notify this list, in case anyone has found them particularly
useful in the past and wants to object to the possible change.  More
details, including my rationale, can be found in the link.

Thanks,

Ryan

-- 
Ryan Curtin    | "Wha' happened?"
ryan at ratml.org |   - Mike LaFontaine