Refactor Bioscrape Core

[WilliamIX]

Currently Lineages is a seperate "module" installed on its own.

System Identification tools should be too.

Bioscrape core has disgustingly long .pyx files which could be split up something like this:

• propensities.pyx
• delays.pyx
• rules.pyx
• simulators.pyx [internally, many simulators reuse the same code which could be refactored into object oriented subfunctions]
• interfaces.pyx
• volumes.pyx [volumes, cell states, volume splitters]
• result_structures.pyx [results objects, etc]
• delay_queues.pyx

After this refactoring, we should make sure that the old imports still work to keep legacy code functional.