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/scripts/yarn-install.ts

@@ -21,11 +21,11 @@ const YARN_PATH =
     : 'yarn' + (WINDOWS ? '.cmd' : '');
 
 Promise.all(
-  PACKAGES.map(pattern =>
+  PACKAGES.map((pattern) =>
     glob(path.join(__dirname, '..', pattern, 'package.json')),
   ),
 )
-  .then(async packages => {
+  .then(async (packages) => {
     const flattenPackages = packages.reduce((acc, cv) => acc.concat(cv), []);
     console.log(
       `Installing dependencies for ${flattenPackages.length} plugins`,
@@ -56,7 +56,7 @@ Promise.all(
   })
   // eslint-disable-next-line
   .then(() => console.log('📦  Installed all plugin dependencies!'))
-  .catch(err => {
+  .catch((err) => {
     console.error(err);
     console.error('❌  Installing plugin dependencies failed.');
     process.exit(1);