Add tests for new LogisticRegression functionality.
Add tests for new LogisticRegression functionality.

theranger/mlpack,ajjl/mlpack,lezorich/mlpack,ranjan1990/mlpack,darcyliu/mlpack,darcyliu/mlpack,darcyliu/mlpack,palashahuja/mlpack,ranjan1990/mlpack,stereomatchingkiss/mlpack,ajjl/mlpack,ajjl/mlpack,lezorich/mlpack,ranjan1990/mlpack,palashahuja/mlpack,theranger/mlpack,stereomatchingkiss/mlpack,theranger/mlpack,stereomatchingkiss/mlpack,palashahuja/mlpack,lezorich/mlpack