HDX: Partitioned graph statistics

[jteresco]

With the first partitioning algorithm coming along, we will want statistics to be able to be reported. Those relevant in scientific computing include:

• load balance (possibly weighted), with max partition size being a key to load balance.
• edge cuts (possibly weighted), can report as surface indices from earlier RPI SCOREC papers: maximum local surface index (most communication that will be needed by any single partition) and global surface index (total communication volume needed).
• Number of connected components in each partition, average, and max across all partitions.

[MikePlekan]

Structure and some stats have been added using the hdxPart.js file

[jteresco]

This functionality is currently implemented as an AV as "Compute Partition Stats". We need to think about a way to make this functionality available only when it is relevant and in a convenient way. Leaving as-is for now, and will revisit as part of Summer Scholars 2023 with @MikePlekan.