Additions/updates to ease Neuron testing

[pgleeson]

• Pops and cells can't have the same ids, so rename the cells to *_comp, e.g. as here: 9ad241a
• GenerateNeuroMLlite.py should generate a "pure" version of intra/interlaminar network etc. with just that argument (and standard nmllite arguments can be used). Additional arguments should be used for analysis, etc. e.g. python GenerateNeuroMLlite.py -interlaminar -analysis, python GenerateNeuroMLlite.py -interlaminar -jnml
• Ensure the same silent syn mod is used for every connection, i.e. not silentSyn_proj__9_46d_STPc.mod, silentSyn_proj__8B_DP.mod, etc.
• Make sure zero weight/non existent connections aren't generated into NML files and so produce more mods to compile
• Investigate how to use rate variable in Neuron's v value - to ease display of activity inside Neuron (or generate 3D Neuron view linked to internal r value)

[pgleeson]

A simple network version works in Neuron (from GenerateNetwork.py) & is much faster, a few optimisations to do though & better visualisation of activity required