Fixed bug in thesaurus where lexical overlap filterign was done AFTER max_neighbours filtering, which results in very small or empty neighbour lists. Also changed the default value of lowercase in Thesaurus (and renamed that parameter).
Fixed tests that broke in 6658686855e
Added more info to stats file (training and testing data). These are usefult for debugging and only take ~300k of disk space for the typical data sizes I am working with at the moment