message: Add: metamask expose `detect` from the module
diff: /* @flow */
  import MetamaskWallet from './class';
  -import { methodCaller, getInpageProvider } from './helpers';
  +import {
  + methodCaller,
  + getInpageProvider,
  + detect as detectHelper,
  +} from './helpers';
  import { staticMethods as messages } from './messages';
  @@ -25,6 +29,20 @@ const metamaskWallet: Object = {
  address: state.selectedAddress,
  });
  }, messages.metamaskNotAvailable),
  + /**
  + * Check if Metamask's injected web3 proxy instance is available in the
  + * global object.
  + *
  + * Makes use of the `detect()` helper, basically it's a wrapper
  + * that exposes it from the module.
  + *
  + * @TODO Add unit test(s)
  + *
  + * @method detect
  + *
  + * @return {boolean} Only returns true if it's available, otherwise it will throw.
  + */
  + detect: async (): Promise<boolean> => detectHelper(),
  };
  export default metamaskWallet;
  