Add focused user mode for speed grader

Minor change to the component to add a button that enables or disables the focused mode for the focusedUser passed into the settings object.

Merge pull request #1287 from hypothesis/dependabot/npm_and_yarn/babel-plugin-transform-async-to-promises-0.8.14

Bump babel-plugin-transform-async-to-promises from 0.8.13 to 0.8.14

Bump preact from 10.0.0-rc.0 to 10.0.0-rc.1

Bumps [preact](https://github.com/developit/preact) from 10.0.0-rc.0 to 10.0.0-rc.1.
- [Release notes](https://github.com/developit/preact/releases)
- [Commits](https://github.com/developit/preact/compare/10.0.0-rc.0...10.0.0-rc.1)
Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Bumps [babel-plugin-transform-async-to-promises](https://github.com/rpetrich/babel-plugin-transform-async-to-promises) from 0.8.13 to 0.8.14.
- [Release notes](https://github.com/rpetrich/babel-plugin-transform-async-to-promises/releases)
- [Commits](https://github.com/rpetrich/babel-plugin-transform-async-to-promises/compare/v0.8.13...v0.8.14)
Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Add edited timestamp to annotation headers

Update the `time` utility module to more closely match
our current conventions. Also make time math consistent
(always use `ms` units), organize for concision and
rename a few references for clarity.

The only functional change is the addition of the string
"ago" to some of the relative time templating.

Refactor annotation events

Remove state logic from root-thread and place it in corresponding stores:

- deleteNewAndEmptyAnnotations moves to drafts and renamed to deleteNewAndEmptyDrafts
- events.BEFORE_ANNOTATION_CREATED's logic moves to createAnnotation in annotations store
- selection store handles REMOVE_ANNOTIONS action directly

Bump eslint from 6.0.1 to 6.1.0

Simplify root thread generation in top-level UI components

Bumps [eslint](https://github.com/eslint/eslint) from 6.0.1 to 6.1.0.
- [Release notes](https://github.com/eslint/eslint/releases)
- [Changelog](https://github.com/eslint/eslint/blob/master/CHANGELOG.md)
- [Commits](https://github.com/eslint/eslint/compare/v6.0.1...v6.1.0)
Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Bump eslint-plugin-react from 7.14.2 to 7.14.3

Merge pull request #1274 from hypothesis/dependabot/npm_and_yarn/karma-coverage-istanbul-reporter-2.1.0

Bump karma-coverage-istanbul-reporter from 2.0.6 to 2.1.0

Bump @octokit/rest from 16.28.5 to 16.28.7

Merge pull request #1278 from hypothesis/dependabot/npm_and_yarn/babel-plugin-transform-async-to-promises-0.8.13

Bump babel-plugin-transform-async-to-promises from 0.8.12 to 0.8.13

Fix typo `bnt` -> `btn` in `SelectionTabs` component

Bumps [babel-plugin-transform-async-to-promises](https://github.com/rpetrich/babel-plugin-transform-async-to-promises) from 0.8.12 to 0.8.13.
- [Release notes](https://github.com/rpetrich/babel-plugin-transform-async-to-promises/releases)
- [Commits](https://github.com/rpetrich/babel-plugin-transform-async-to-promises/compare/v0.8.12...v0.8.13)
Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Bumps [eslint-plugin-react](https://github.com/yannickcr/eslint-plugin-react) from 7.14.2 to 7.14.3.
- [Release notes](https://github.com/yannickcr/eslint-plugin-react/releases)
- [Changelog](https://github.com/yannickcr/eslint-plugin-react/blob/master/CHANGELOG.md)
- [Commits](https://github.com/yannickcr/eslint-plugin-react/compare/v7.14.2...v7.14.3)
Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Bumps [@octokit/rest](https://github.com/octokit/rest.js) from 16.28.5 to 16.28.7.
- [Release notes](https://github.com/octokit/rest.js/releases)
- [Commits](https://github.com/octokit/rest.js/compare/v16.28.5...v16.28.7)
Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Bumps [karma-coverage-istanbul-reporter](https://github.com/mattlewis92/karma-coverage-istanbul-reporter) from 2.0.6 to 2.1.0.
- [Release notes](https://github.com/mattlewis92/karma-coverage-istanbul-reporter/releases)
- [Changelog](https://github.com/mattlewis92/karma-coverage-istanbul-reporter/blob/master/CHANGELOG.md)
- [Commits](https://github.com/mattlewis92/karma-coverage-istanbul-reporter/compare/v2.0.6...v2.1.0)
Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Since an Angular digest cycle is triggered whenever Redux store state
changes, we can simplify the top-level component controllers in the UI
by making `vm.rootThread` a method which generates the top-level thread
when called.

Since `rootThread.thread` memoizes based its input, thread recalculation
won't happen more often than necessary.

This change should also make it easier to migrate these components to
Preact/React in future.

Move tab counts to store

Previously, the number of annotations in each tab and the currently
selected tab were passed from the sidebar into the search-status-bar
and selection-tab components. Now, they are  grabbed from the store.

Remove unused ng component wrappers

The only consumers of these components have been converted to Preact

This component has been migrated to Preact

Add react selection-tabs component

Only allow one group's submenu to be expanded at a time

 - Set `display: none` on the content of a Slider when it is fully
   collapsed, so that the DOM nodes are removed from keyboard navigation
   order

 - Make the collapse animation work more reliably across browsers by
   forcing a synchronous layout after changing the DOM node's height
   from "auto" to a fixed pixel size. In Chrome and Firefox neither
   `setTimeout(callback, 0)` nor `requestAnimationFrame` reliably
   ensured that the browser "saw" the change from "auto" =>
   fixed height instead of "seeing" a change from "auto" directly to 0,
   which does not get animated