Load neuron <> neuron and neuron <> region for L1EM

[admclachlan]

We now have a complete (up to 'The connectome of an insect brain') L1EM CATMAID, can now import connectomics for L1EM. Should first confirm we want this and then confirm how to load. Currently would be CATMAID > TSV > ROBOT templates.

[admclachlan]

TODO

• import regions - make sure have classes
• calculate region connectivity - try API