[FEA] Support Out of Core Kmeans Clustering

[tarang-jain]

MiniBatchKMeans is a scalable variant of the classic K-Means clustering algorithm. It uses small, random subsets (mini-batches) of the data in each iteration.

[betatim]

Please add a description with some context to the issue

[aamijar]

Any updates on this issue, and whether we still need more information?

[csadorf]

@tarang-jain Please add a bit more context and motivation to the issue description.