Latest update; using a single synapse for N connections

E.g. <expTwoSynapse id="exc_syn_4conns" ...> with gbase scaled
accordingly, as opposed to using 4 connections
Merge branch 'master' of github.com:openworm/CElegansNeuroML

* 'master' of github.com:openworm/CElegansNeuroML:
  Update README.md