Save encrypted keystore into local storage

eth-hot-wallet-store.js

import localStore from 'store/dist/store.modern';

/* keystore will be saved to local storage under this key */
export const localStorageKey = 'ks';

/**
 * Save wallet to localStorage
 */
export function* saveWalletS() {
  try {
    const ks = yield select(makeSelectKeystore());
    
    // Add app specific metadeta such as version and date
    const dump = {
      ver: '1', 
      saved: new Date().toISOString(),
      ks: ks.serialize(),
    };

    localStore.set(localStorageKey, dump);

    yield put(saveWalletSuccess());
  } catch (err) {
    const errorString = `${err.message}`;
    yield put(saveWalletError(errorString));
  }
}