ENH: Compute and plot network statistics of structural and functional connectivity matrices

[sebastientourbier]

Goal
Serve as quality assurance

Tasks

• Computes and plots of connectome-specific summary statistics as in ndmg:
  • Implement a load_graph() which takes the full path of the connectome to load
  • Implement a load_graphs() which takes the BIDS root directory, the output directory, the (sub)list, and the parcellation scheme. It will call load_graph() for each subject / session / parcellation scale.
  • Implement a compute_network_metrics() which:
    1. differentiate structural and functional connectivity matrices and
    2. compute for each connectivity matrix scale network measures and statistics (Number of non-zero edges, Max Local Statistic Sequence, Clustering Coefficients, Degree sequence, Edge weight sequence, , Eigen value, betweenness centrality, mean/median connectome)
• Integration of plots in the processing summary report of the diffusion pipeline (ENH: Processing summary report for diffusion pipeline #10)