[CORL-678] Transition to eslint (#2634)

* chore: setup eslint

* chore: tslint checks with types & check for import order

* chore: complete eslint transition

* fix: tests

* fix: linting after rebase, faster lint for lint-staged

* chore: remove line

* fix: lint rules

* feat: add a11y linter and fix errors

* fix: tests

src/types/fluent.d.ts

@@ -1,4 +1,4 @@
-// tslint:disable:max-classes-per-file
+/* eslint-disable max-classes-per-file */
 
 // Allowing loading fluent files.
 declare module "*.ftl";

src/types/metascraper.d.ts

@@ -18,25 +18,25 @@ declare module "metascraper" {
 
 declare module "metascraper-author" {
   import { Rules } from "metascraper";
-  export default function(): Rules;
+  export default function def(): Rules;
 }
 
 declare module "metascraper-date" {
   import { Rules } from "metascraper";
-  export default function(): Rules;
+  export default function def(): Rules;
 }
 
 declare module "metascraper-description" {
   import { Rules } from "metascraper";
-  export default function(): Rules;
+  export default function def(): Rules;
 }
 
 declare module "metascraper-image" {
   import { Rules } from "metascraper";
-  export default function(): Rules;
+  export default function def(): Rules;
 }
 
 declare module "metascraper-title" {
   import { Rules } from "metascraper";
-  export default function(): Rules;
+  export default function def(): Rules;
 }

src/types/react-relay-network-modern.d.ts

@@ -1,4 +1,4 @@
-/* tslint:disable */
+/* eslint-disable */
 
 // TODO: send a PR to DefinitelyTyped.