Merge pull request #1 from escherba/dev

add topic extraction, refactor
Merge branch 'dev'
be more path-independent
use normalizer
use roc_auc scoring
add sample output to README
use UTF-8 encoding for top features
factor out L1 feature-selector wrapper
Merge pull request #2 from escherba/use_normalizer_step

Use normalizer step
added a radial kernal and put the nice plot in
added the plots right
Merge pull request #3 from escherba/radial_kernal

add plotting system