Update prettier config and reformat

Here's the discussion summary:
- single quote, because that's what I'm used to in the JS world
- trailing comma, to avoid unnecessary git changes
- print-width 120, because 120 still doesn't require to scroll horizontally, and vertical space is precious

4 files changed, 16 insertions, 35 deletions

diff --git a/frontend/src/components/errors/Error404.js b/frontend/src/components/errors/Error404.js
index bf12453d..32ab8e8d 100644
--- a/frontend/src/components/errors/Error404.js
+++ b/frontend/src/components/errors/Error404.js
@@ -1,5 +1,5 @@
-import React from "react";
-import { Link } from "react-router";
+import React from 'react';
+import { Link } from 'react-router';
 
 const Error404 = () => (
   <div>
diff --git a/frontend/src/components/gameList.js b/frontend/src/components/gameList.js
index e1d011e1..f3a0d381 100644
--- a/frontend/src/components/gameList.js
+++ b/frontend/src/components/gameList.js
@@ -1,7 +1,7 @@
-import React from "react";
-import { Flex } from "reflexbox";
-import { Text, Space, Button } from "rebass";
-import Immutable from "seamless-immutable";
+import React from 'react';
+import { Flex } from 'reflexbox';
+import { Text, Space, Button } from 'rebass';
+import Immutable from 'seamless-immutable';
 
 const GameList = props => (
   <div>
diff --git a/frontend/src/components/modals/username.js b/frontend/src/components/modals/username.js
index 826bce85..c00262a7 100644
--- a/frontend/src/components/modals/username.js
+++ b/frontend/src/components/modals/username.js
@@ -1,37 +1,18 @@
-import React from "react";
-import {
-  Overlay,
-  Panel,
-  PanelHeader,
-  PanelFooter,
-  Button,
-  Input,
-  Close,
-  Space
-} from "rebass";
+import React from 'react';
+import { Overlay, Panel, PanelHeader, PanelFooter, Button, Input, Close, Space } from 'rebass';
 
 const Modal = ({ modalOpen, toggleModal }) => (
-  <Overlay open={modalOpen} onDismiss={toggleModal("usernameModal")}>
+  <Overlay open={modalOpen} onDismiss={toggleModal('usernameModal')}>
     <Panel theme="info">
       <PanelHeader>
         What's your username ?
         <Space auto />
-        <Close onClick={toggleModal("usernameModal")} />
+        <Close onClick={toggleModal('usernameModal')} />
       </PanelHeader>
-      <Input
-        label="Username"
-        name="username"
-        placeholder="Cesar92"
-        rounded
-        type="text"
-      />
+      <Input label="Username" name="username" placeholder="Cesar92" rounded type="text" />
       <PanelFooter>
         <Space auto />
-        <Button
-          theme="success"
-          onClick={toggleModal("usernameModal")}
-          children="Ok"
-        />
+        <Button theme="success" onClick={toggleModal('usernameModal')} children="Ok" />
       </PanelFooter>
     </Panel>
   </Overlay>
diff --git a/frontend/src/components/playerList.js b/frontend/src/components/playerList.js
index b7f6e7c3..1a68b067 100644
--- a/frontend/src/components/playerList.js
+++ b/frontend/src/components/playerList.js
@@ -1,7 +1,7 @@
-import React from "react";
-import { Flex } from "reflexbox";
-import { Text } from "rebass";
-import Immutable from "seamless-immutable";
+import React from 'react';
+import { Flex } from 'reflexbox';
+import { Text } from 'rebass';
+import Immutable from 'seamless-immutable';
 
 const PlayerList = props => (
   <div>