Merge remote-tracking branch 'marinka/master'
Added Mahalanobis distance
Merge remote-tracking branch 'marinka/master'
Test for sparse matrices for Euclidean
Merge remote-tracking branch 'marinka/master'
Merge remote-tracking branch 'niko/master'
Added test for Mahalanobis distance - inverse given
Merge remote-tracking branch 'niko/master'
Added Spearman and absolute Spearman distance