Initialization of the mixture model

The parameters of the model are initialized by sampling from the uniform distribution of desired range. The mixing coefficients are initialized to be equal. The model is written to a file or standard output. An example command is

./bmix_init --clusters 2 --data-dim 3 \
     --model tiny.model

which initializes a model with 2 component distributions for modeling 3-dimensional 0-1 data and writes the model to a file.