fix(app): error handling improved

[neSpecc]

Problem

If API will return error on app initialization, the whole app will break

Cause

1. We don't have try-catch handling in many places, especially in app initialization
2. We don't have common error handling pattern
3. GraphQL API can return both response.data and response.errors. In this case data is ignored at the moment since errors are being thrown.

Solution

1. We don't need to throw error from API. Just return it as well as data. It should be handled on a store/component level then.
2. To not to break existing error handling, I've added explicit flag allowErrors to a single place (FETCH_INITIAL_DATA mutation) I touched.
3. All API errors will be sent to Hawk.

Also

1. Service Worker and PWA-plugin are removed to prevent problems with caching.
2. Version now will be added to static file names on build (also, to prevent caching)
3. Now we can track errors via Hawk not only on vue-level. The useErrorTracker() composable is created for that.
4. Few minor fixes