Uppercase THE to Capitalize The (#638)

Author: ChangJoo Park(박창주)

src/v2/guide/join.md

@@ -12,7 +12,7 @@ Now we'll answer both what the community can do for and what you can do for the
 
 ### Get Support
 
-- [Forum](http://forum.vuejs.org/): THE best place to ask questions and get answers about Vue and its ecosystem.
+- [Forum](http://forum.vuejs.org/): The best place to ask questions and get answers about Vue and its ecosystem.
 - [Gitter Channel](https://gitter.im/vuejs/vue): A place for devs to meet and chat. You can ask questions here too, but the forum is the better platform, since the discussions are threaded.
 - [Github](https://github.com/vuejs): If you have a bug to report or feature to request, that's what the GitHub issues are for. We also welcome pull requests!