Massive refactor

- Use contextual namespaces within Flarum\Core
- Clean up and docblock everything
- Refactor Activity/Notification blueprint stuff
- Refactor Formatter stuff
- Refactor Search stuff
- Upgrade to JSON-API 1.0
- Removed “addedPosts” and “removedPosts” relationships from discussion
API. This was used for adding/removing event posts after renaming a
discussion etc. Instead we should make an additional request to get all
new posts

Todo:
- Fix Extenders and extensions
- Get rid of repository interfaces
- Fix other bugs I’ve inevitably introduced

src/Core/Exceptions/ValidationFailureException.php

@@ -1,19 +1,37 @@
 <?php namespace Flarum\Core\Exceptions;
 
+use Exception;
 use Illuminate\Support\MessageBag;
+use DomainException;
 
-class ValidationFailureException extends \InvalidArgumentException
+class ValidationFailureException extends DomainException
 {
+    /**
+     * @var MessageBag
+     */
     protected $errors;
 
+    /**
+     * @var array
+     */
     protected $input = array();
 
+    /**
+     * @param string $message
+     * @param int $code
+     * @param Exception $previous
+     */
     public function __construct($message = '', $code = 0, Exception $previous = null)
     {
         parent::__construct($message, $code, $previous);
+
         $this->errors = new MessageBag;
     }
 
+    /**
+     * @param MessageBag $errors
+     * @return $this
+     */
     public function setErrors(MessageBag $errors)
     {
         $this->errors = $errors;
@@ -21,11 +39,18 @@ class ValidationFailureException extends \InvalidArgumentException
         return $this;
     }
 
+    /**
+     * @return MessageBag
+     */
     public function getErrors()
     {
         return $this->errors;
     }
 
+    /**
+     * @param array $input
+     * @return $this
+     */
     public function setInput(array $input)
     {
         $this->input = $input;
@@ -33,6 +58,9 @@ class ValidationFailureException extends \InvalidArgumentException
         return $this;
     }
 
+    /**
+     * @return array
+     */
     public function getInput()
     {
         return $this->input;