Go on implementing sampling for initialization of topic model

now implemented the calculation of topics which have a small count which will be deleted
additionally there was a deletion of commented code which was not used
Add comments to ParallelTopicModel to understand code better
Refactor (sort the functions and add some comments for clarity)
Delete unused OnlineLDA classes
Implement the calculation of smoothed topic counts for topic model initialization

by adding beta to the written file about typeTopicCounts
by reading beta from that file
also did some refactoring (delete unused methods, because they were only used by online LDA)
Move evaluation to package org.twittersearch.app.evaluation

fits better to the other packages