Convert imports to ES6 from CommonJS

This is needed because `require()` means something different in webpack - it ends up importing the module as something we didn't expect (and is occasionally async)

src/Unread.js

@@ -16,7 +16,7 @@ limitations under the License.
 
 import {MatrixClientPeg} from "./MatrixClientPeg";
 import shouldHideEvent from './shouldHideEvent';
-const sdk = require('./index');
+import * as sdk from "./index";
 
 module.exports = {
     /**