Adapting tests to backend changes in text analysis

Adding test file

Bug fixing: create source failed when using unicode arguments

Ensuring unique ordering in MultiVote categorical combinations

Changing last test data for clusters according to backend changes

Bug fixing: changing tests to compare utf-8 encoded binary streams

Changes in doc, license and naming constant

Adding median based predictions to ensembles

Bug fixing: multimodel median predictions failed

Adding support for median in multimodel's batch prediction method