[Bug report] simulations should not silently proceed if mechanisms cannot be inserted

[sanjayankur31]

Describe the bug

If one runs a netpyne script but forgets to compile the mod files, the simulation gives an error, but still proceeds. This is unexpected behaviour and a message is not quite enough because it'll likely be buried in lots of other messages that the simulation produces:

This is the code:

netpyne/netpyne/cell/compartCell.py

Line 375 in 31a5f13

"ERROR: Some mechanisms and/or ions were not inserted (for details run with cfg.verbose=True). Make sure the required mod files are compiled."

It should throw an exception and stop, because the model/simulation with missing mechanisms is just wrong?