Fix the default config description (#38)

* There's no auth stuff in here

* `now` -> `Now`

* Add missing `'`

* Mention `now config help`

src/get-default-auth-cfg.js

@@ -1,6 +1,6 @@
 const getDefaultAuthCfg = () => ({
   _:
-    'This is your now credentials file. DONT SHARE! More: https://git.io/now-global-config',
+    'This is your Now credentials file. DON\'T SHARE! More: https://git.io/now-global-config',
   credentials: []
 })
 

src/get-default-cfg.js

@@ -1,6 +1,6 @@
 const getDefaultCfg = () => ({
   _:
-    'This is your now credentials file. DONT SHARE! More: https://git.io/now-global-config'
+    'This is your Now config file. See `now config help`. More: https://git.io/now-global-config'
 })
 
 module.exports = getDefaultCfg