[REF] owl: reorganize exports, remove registry, remove web example

closes #38

src/index.ts

@@ -1,7 +1,6 @@
 export { Component, PureComponent } from "./component";
 export { EventBus } from "./event_bus";
 export { QWeb } from "./qweb";
-export { Registry } from "./registry";
 export { connect, Store } from "./store";
 import * as _utils from "./utils";