webglapp: renamed "Branch centrality" to "Slab centrality"
Arbor: new function nodesDistanceTo, which generalizes former edgeCountToRoot,
which is now renamed to nodesOrderFrom.
Ciruit graph analysis: set numeric.epsilon to a less small value than default
which prevents the occasional failures to find the eigenvalues of the graph
laplacian of the adjacency matrix.
Merge remote-tracking branch 'origin/master'