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/build-utils.ts

@@ -26,7 +26,7 @@ async function mostRecentlyChanged(
     recursiveReaddir,
   )(dir, ignores);
   return files
-    .map(f => fs.lstatSync(f).ctime)
+    .map((f) => fs.lstatSync(f).ctime)
     .reduce((a, b) => (a > b ? a : b), new Date(0));
 }
 
@@ -45,7 +45,7 @@ export function compileDefaultPlugins(
     defaultPluginDir,
     {force: true, failSilently: false, recompileOnChanges: false},
   )
-    .then(defaultPlugins =>
+    .then((defaultPlugins) =>
       fs.writeFileSync(
         path.join(defaultPluginDir, 'index.json'),
         JSON.stringify(
@@ -187,7 +187,7 @@ export function buildFolder(): Promise<string> {
         resolve(buildFolder);
       }
     });
-  }).catch(e => {
+  }).catch((e) => {
     die(e);
     return '';
   });
@@ -205,7 +205,7 @@ export function getVersionNumber() {
 export function genMercurialRevision(): Promise<string | null> {
   return spawn('hg', ['log', '-r', '.', '-T', '{node}'], {encoding: 'utf8'})
     .then(
-      res =>
+      (res) =>
         (res &&
           (typeof res.stdout === 'string'
             ? res.stdout