Helper functions to retrieve information from different k values

[fanavarro]

Previously we had the following functions retrieving information from the optimal k:

• annotateClustersByMetric: include the cluster ID in each individual according to the optimal clustering.
• getMetricRangeByCluster: Get the ranges of a metric according to each cluster of the optimal clustering.

Now, I have renamed these functions as follows:

• annotateClustersByMetric -> annotateOptimalClustersByMetric
• getMetricRangeByCluster -> getMetricOptimalRangeByCluster

And I have included functions to retrieve the same information for a k range and not only for the optimal k. These functions have the old names. So, finally, the new functionality is:

• annotateOptimalClustersByMetric: include the cluster ID in each individual according to the optimal clustering.
• getMetricOptimalRangeByCluster: Get the ranges of a metric according to each cluster of the optimal clustering.
• annotateClustersByMetric: include the cluster ID in each individual according to different values of k.
• getMetricRangeByCluster: Get the ranges of a metric according to different values of k.