Add a prefix to actions according to the state name

[a-astrouski]

pros:

1. Unique action name for actions in another state.

For example:

{type: "friends/GET_USERS"}
{type: "users/GET_USERS"}
{type: "suggestedUsers/GET_USERS"}
{type: "guests/GET_USERS"}

In this case, the probability that you will create an action that already exists in another state is reduced.

2. Debugging will be more convenient, because you can filter actions by state in redux devtools or determine in which state this action exists.

[remotenode]

@d1mon1k thanks for your proposal.

Adding prefix for each action type manually seems too verbose, it would be nice if we could add prefix somehow under the hood, for example, when dispatching action