Potential improvements to state management performance, possibly making it pluggable

[maier49]

For large state stores, things like ImmutableJS are recommended by the redux team as a way to improve update performance. On the other hand ImmutableJS can be quite slow for operations like finding a value.

Making the actual state management portion of the store pluggable would allow a user to implement something that suits their needs without making additional assumptions.

Alternatively, or in addition to this, we could look into general performance improvements such as doing updates in a web worker, since we completely control the "reduction" part of the store life cycle.