message: Update: docs after `infura` to async refactor
diff: @@ -304,7 +304,7 @@ const providerDefaults = metamask();
  ### `etherscan`
  ```js
  -etherscan([ProviderArguments: Object])
  +await etherscan([ProviderArguments: Object])
  ```
  This method returns a `Promise`, which after resolving, will return a provider instance object, instantiated with the necessary prop fields.
  @@ -329,10 +329,10 @@ const provider = await etherscan({
  ### `infura`
  ```js
  -infura([ProviderArguments: Object])
  +await infura([ProviderArguments: Object])
  ```
  -This method returns an provider instance object, instantiated with the necessary prop fields.
  +This method returns a `Promise`, which after resolving, will return a provider instance object, instantiated with the necessary prop fields.
  Even though it will work out of the box, it is highly recommended that you pass in at least the `apiKey` key via the `walletArguments` object. A new token for the Infura API can be generated by [signing up for the service](https://infura.io/signup).
  @@ -343,7 +343,7 @@ The only two _(optional)_ props that this method will take are `network` and `ap
  ```js
  import { infura } from 'colony-wallet/providers';
  -const provider = infura({
  +const provider = await infura({
  network: 'homestead',
  apiKey: '<your-token-key>',
  });
  @@ -383,7 +383,7 @@ const provider = jsonRpc({
  ### `autoselect`
  ```js
  -autoselect([providersList: Array<function|Object>])
  +await autoselect([providersList: Array<function|Object>])
  ```
  This is just a helper method that goes through a list of providers _(both generator methods and already instantiated provider objects)_ and selects the first one available.
  