Topological NBLAST

[dokato]

This (long overdue) PR proposed topological NBLAST. A modification that introduced 2 critical changes:

1. Directed dotprop vectors (pointing to soma/root).
2. Scaling dotprops by topological node features.

In order to run topoNBLAST, one nedds to compute the topodotprops with nat:

tdps = dotprops(nrns, topo=T)

then it's possible to call:

nabat <- nblast_allbyall(tdps, version=1, sd=10, UseTopo=T)

It's recommended to use version 1 of scoring as it's more sensitive to orientation changes and currently there's no scoring matrix for topo version.

To work correctly, it required topo dotporps to be computed first: natverse/nat#502