static_synapse -> nest:static_synapse

[pgleeson]

As pointed out by @apdavison, it would make more sense to use nest:static_synapse in BMTK (and standard Sonata) in the same way as the Nest cell nest:iaf_psc_alpha is defined. Example:

sonata/examples/300_pointneurons/build_network.py

Line 91 in ad1d46a

model_template='static_synapse',

Currently the PyNN import of Sonata only supports nest:static_synapse