Merge pull request #69 from emsiepopples/master

Added functionality to lda_analysis.py and nb_kfolds.py; new top_topics.py code
lsi.py modified to produce topic prob-document matrix as well as topic label vector
Merge pull request #70 from ilanfri/master

lsi.py rewritten
Merge branch 'master' of https://github.com/s2ds-kpmg1/kpmg1