Core framework refactoring

[colinbdclark]

This pull request contains a significant amount of refactoring to the internals of Flocking, including:

• Introduces new flock.modelSynth grade as a connector to Infusion's model relay system.
• Improves performance by using stateless, closure-less functions in the sample generation pipeline
• Refactors flock.nodeList into a collection of plain functions that operate on decoupled state.
• Reduces dependence within Flocking on references to the Flocking shared environment (in favour of IoC references which can be overridden by users)
• Updates dependency versions, sourcing them all from npm instead of Bower
• Fixes bugs in random and sequencer unit generators