mixture model training added; EM for mixture model added

- EM for mixture model
- mixture model training
- unittest for mixture model with gaussian distributions 
@iglesiasg sorry couldn't reply earlier. I have very limited access to
internet. I will get back to addressing your comments as soon as possible.
Sorry for yhr delay again
 On 7 Aug 2014 03:22, "Fernando Iglesias" <notifications@github.com> wrote:

> In src/shogun/distributions/EMMixtureModel.h:
>
> > + * of the authors and should not be interpreted as representing official policies,
> > + * either expressed or implied, of the Shogun Development Team.
> > + */
> > +
> > +#ifndef _EMMIXTUREMODEL_H__
> > +#define _EMMIXTUREMODEL_H__
> > +
> > +#include <shogun/lib/config.h>
> > +#include <shogun/distributions/EMBase.h>
> > +#include <shogun/distributions/MixModelData.h>
> > +
> > +namespace shogun
> > +{
> > +template class CEMBase<MixModelData>;
> > +
> > +/** @brief This is implementation of EM specialized for Mixture models.
>
> Can we get a citation for the reference you have used to implement the EM
> algorithm here?
>
> —
> Reply to this email directly or view it on GitHub
> <https://github.com/shogun-toolbox/shogun/pull/2448/files#r15923397>.
>