This backports 0b888acfd4

Possibly the cause of #5379, #5377

Do NOT send "delete" through streaming API when unmerging from
home timeline. "delete" implies that the original status was
deleted, which is not true!

* Move ancestors/descendants out of timelines reducer

* Refactor timelines reducer

All types of timelines now have a flat structure and use the same
reducer functions and actions

* Reintroduce some missing behaviours

* Fix wrong import in reports

* Fix includes typo

* Fix issue related to "next" pagination in timelines and notifications

* Fix bug with timeline's initial state, expandNotifications

This prevents `next` state from being overridden on the loading *new* statuses.

because it may causes flicker on the conversation when it contains blocked/muted user's status.

We use `/api/v1/statuses/{id}/context` to obtain status ids in the
conversation which filters blocked/muted user, but also uses internal
cache constructed from `in_reply_to_id` by `normalizeStatus()` in
`reducers/timelines.js` on each status loading which doesn't filter.

So statuses appears in conversation if those are cached, even those
statuses are from blocked/muted user. Then context cache will be updated
with the result of the context API and those statuses will be removed.

I have left the `normalizeStatus()` function itself which is called many
functions in the file as a placeholder for now, but maybe it should be
removed completely.

This will reduce requests on who have only few statuses.

- Use next link header to detect more items from first request
- Omit next link header if result items are fewer than requested count
(It had omit it only if result was empty before)

* Add load more button for large screens
* Fix `next` state value on the first loading
* Don't load if `isLoading || !hasMore`
* Start load on near the bottom

* Add semi to ESLint rules

* Add padded-blocks to ESLint rules

* Add comma-dangle to ESLint rules

* add config/webpack and storyboard

* add streaming/

* yarn test:lint -- --fix

* Add account media gallery view to web UI

* Link media view from account dropdown

* Adjust link

* Replace browserify with webpack

* Add react-intl-translations-manager

* Do not minify in development, add offline-plugin for ServiceWorker background cache updates

* Adjust tests and dependencies

* Fix production deployments

* Fix tests

* More optimizations

* Improve travis cache for npm stuff

* Re-run travis

* Add back support for custom.scss as before

* Remove offline-plugin and babili

* Fix issue with Immutable.List().unshift(...values) not working as expected

* Make travis load schema instead of running all migrations in sequence

* Fix missing React import in WarningContainer. Optimize rendering performance by using ImmutablePureComponent instead of
React.PureComponent. ImmutablePureComponent uses Immutable.is() to compare props. Replace dynamic callback bindings in
<UI />

* Add react definitions to places that use JSX

* Add Procfile.dev for running rails, webpack and streaming API at the same time

refreshes on navigation

"whole known network" which is what public timeline used to be

Only domain blocks with suspend severity will block PuSH subscriptions
Silenced accounts should not appear in conversations unless followed

skip ActionCable for follow/unfollow/block events, instead clear UI from
blocked account's posts instantly if block request succeeds. Add forgotten
i18n for sensitive content

This makes the UI appear less laggy. After all, the status *is* created
right there and then, it's the distribution to home timelines that can take
a while

Also fix reloading of timelines after merge-type events

entire timelines (only fetch since last known ID). Side effect: account
timelines no longer update in real-time

Also upgrade react-redux to latest version. This is a performance update

Track relationship in redux state. Display follow/unfollow and following-back
information on account view (unstyled)