feat: Improved table of contents (#1223)

* feat: New table of contents

* fix: Hide TOC in edit mode

* feat: Highlight follows scroll position

* scroll tracking

* UI

* fix: Unrelated css fix with long doc titles

* Improve responsiveness

* feat: Add keyboard shortcut access to TOC

* fix: Headings should reflect content correctly when viewing old document revision

* flow

* fix: Persist TOC choice between sessions

package.json

@@ -55,6 +55,7 @@
     "url": "git+ssh://git@github.com/outline/outline.git"
   },
   "dependencies": {
+    "@rehooks/window-scroll-position": "^1.0.1",
     "@sentry/node": "^5.12.2",
     "@tippy.js/react": "^2.2.2",
     "@tommoor/remove-markdown": "0.3.1",
@@ -119,7 +120,7 @@
     "mobx-react": "^5.4.2",
     "natural-sort": "^1.0.0",
     "nodemailer": "^4.4.0",
-    "outline-icons": "^1.13.0",
+    "outline-icons": "^1.14.0",
     "oy-vey": "^0.10.0",
     "pg": "^6.1.5",
     "pg-hstore": "2.3.2",