chore: add eslint and cleanup (#118)

* refactor: modified existing react imports to conform with the recommended approach of not using the default export directly, since it will be deprecated in one of the future releases. see https://reactjs.org/blog/2020/09/22/introducing-the-new-jsx-transform.html for more info. note: react types don't require importing of react.
refactor: cleaned up some of the imports

* feat: added eslint and fixed all the errors/warning. eslint can now be invoked by running "npm run lint".
chore: updated .gitignore not to include unnecessary artefacts.
refactor: re-organized some of the imports.

* refactor: converted remaining few typed functional components to proper prop argument structure.

* fix: fixed small react-query invalidation bug for the FilterDetails component.

Co-authored-by: anonymous <anonymous>

web/src/screens/auth/logout.tsx

@@ -13,7 +13,7 @@ function Logout() {
 
     useEffect(
         () => {
-            APIClient.auth.logout().then(r => {
+            APIClient.auth.logout().then(() => {
                 setAuthContext({ username: "", isLoggedIn: false });
                 removeCookie("user_session");
                 history.push('/login');