prettier 2

Summary:
Quick notes:

- This looks worse than it is. It adds mandatory parentheses to single argument lambdas. Lots of outrage on Twitter about it, personally I'm {emoji:1f937_200d_2642} about it.
- Space before function, e.g. `a = function ()` is now enforced. I like this because both were fine before.
- I added `eslint-config-prettier` to the config because otherwise a ton of rules conflict with eslint itself.

Close https://github.com/facebook/flipper/pull/915

Reviewed By: jknoxville

Differential Revision: D20594929

fbshipit-source-id: ca1c65376b90e009550dd6d1f4e0831d32cbff03

desktop/.eslintrc.js

@@ -24,7 +24,7 @@ const prettierConfig = {
 module.exports = {
   parser: 'babel-eslint',
   root: true,
-  extends: 'fbjs',
+  extends: ['fbjs', 'prettier'],
   plugins: [
     ...fbjs.plugins,
     'header',
@@ -43,8 +43,6 @@ module.exports = {
     'prefer-const': [2, {destructuring: 'all'}],
     'prefer-spread': 1,
     'prefer-rest-params': 1,
-    'max-len': 0, // lets prettier take care of this
-    indent: 0, // lets prettier take care of this
     'no-console': 0, // we're setting window.console in App.js
     'no-multi-spaces': 2,
     'prefer-promise-reject-errors': 1,