Make it easier to avoid compressing decoders.
Put simulation cleanup code in a try:finally block.
Merge branch 'master' into cleanup-on-fail

Conflicts:
	nengo_spinnaker/simulator.py
Allow simulation with no Nodes.

 - flake8
Merge branch 'master' into opt-compress

Conflicts:
	nengo_spinnaker/utils/tests/test_decoders.py
Don't appstop if loading hasn't taken place.
Merge branch 'cleanup-on-fail' of github.com:ctn-waterloo/nengo_spinnaker into cleanup-on-fail

Conflicts:
	nengo_spinnaker/simulator.py
Merge pull request #82 from ctn-waterloo/cleanup-on-fail

Put simulation cleanup code in a try:finally block.
Merge pull request #85 from ctn-waterloo/opt-compress

Decoder compression improvements
Merge in from master.

Cherry picked from b9c1e7f034197

Conflicts:
	nengo_spinnaker/ensemble_vertex.py
	nengo_spinnaker/simulator.py
Merge branch 'master' into multi-inputs

Conflicts:
	nengo_spinnaker/builder.py
	nengo_spinnaker/edges.py
	nengo_spinnaker/ensemble_vertex.py
	nengo_spinnaker/simulator.py
	nengo_spinnaker/utils/probes.py
	nengo_spinnaker/value_sink_vertex.py
	setup.py
	spinnaker_components/Makefile
	spinnaker_components/value_sink/Makefile
	spinnaker_components/value_sink/value_sink.c
	spinnaker_components/value_sink/value_sink.h
Merge pull request #92 from ctn-waterloo/multi-inputs

Multiple Inputs for a Executable
Merge branch 'master' into jamie_pes

Conflicts:
	spinnaker_components/value_sink/value_sink.c