added the ability to deal with multiple labels
the combined dataset now has a column for the label. it is 0, by default
the probability matrix's 4th column is an indicator of the label
the dataset that is fitted with gaussians begins with the 5th column
now, also extended the function to allow the variables that are saved to
have a tag
the probability calculation has been modified to start looking from the
fifth column instead of the fourth
the normalization takes places from 5:end rather than 4:end