Do not add injectedReducers property to a store

[xprazak2]

Adding the injectedReducers property to a store can cause problems when testing connected components using snapshots.

When adding a new reducer, each snapshots will need to be regenerated because the injectedReducers property on injected store changes. This will become painful as an application grows.

If we want to expose the injectedReducers to the outside world, I can add a function to a store that does it for us.

Let me know what you think.

[ares]

what's the status here?

[xprazak2]

waiting for review

[ares]

@randallknutson would you mind taking a look?