Be able to specify a netlist and run, without having to fork

[trentmc]

Is your feature request related to a problem? Please describe.
If someone wants to run a simulation for a different system, right now they need to fork. This means any improvements they make, and new models they incorporate, won't easily make it into the core TokenSPICE codebase -- a lost opportunity to grow an amazing system.

Describe the solution you'd like
Be more like SPICE proper: users can specify a netlist, and run it, without having to change the code itself. Support more building blocks over time.

Bonus: This will help in doing #29 because it means the system can have both Ocean V3 models and V4 models at once.

[trentmc]

Done:)