Updated the cluster() function to change the current
clustering metric it is using if it is not suitable for your
data.
read_dist() and cluster() will now
return objects with class name “distance_object”, and “mothur_cluster”
respectively. This will ensure the returned object can be differentiated
between other R objects.
Fixed memory leaks that were found using Valgrind.
cluster() returning duplicate cluster names when
using method = “opticlust.”