[WIP] Mutation interpolation

- [ ] Pass which types of mutations are allowed in `network.mutation`
- [ ] Interpolation helper functions

Mutation Distance Interpolation for 
- [ ] `MutateConnectionWeights` ConnectionMutationRate and mutationDelta
- [ ] `MutateNodeParameters` nodeMutationRate
- [ ] `node` parameterMutation chance
- [ ] `node` mutatableParameters

FM Connections
- [ ] new ConnectableParam objects in all affected nodes
```
{
  name: <string>
  deltaRange: {
    min: [y0, y1],
    max: [y0, y1]
  },
  randomRange: {
    min: <number>,
    max: <number>
  }
}
```
- [ ] new ConnectableParams used during fm `NoteOscillator` creation in `network.addOscillator`
- [ ] to/from JSON work correctly?

Other
- [ ] Tests