Move System::jsonError to BaseModule->jsonError

- This will ensure headers set in BaseModule->run will be carried in jsonError scenarios
- Make BaseApi->checkThrottleLimit an object method to use BaseModule->jsonError
- Deprecate jsonError() method in Core\System

src/Module/Api/Mastodon/Proofs.php

@@ -34,6 +34,6 @@ class Proofs extends BaseApi
 	 */
 	protected function rawContent(array $request = [])
 	{
-		System::jsonError(404, ['error' => 'Record not found']);
+		$this->jsonError(404, ['error' => 'Record not found']);
 	}
 }

src/Module/Api/Mastodon/Statuses.php

@@ -263,7 +263,7 @@ class Statuses extends BaseApi
 			$item['gravity']     = Item::GRAVITY_COMMENT;
 			$item['object-type'] = Activity\ObjectType::COMMENT;
 		} else {
-			self::checkThrottleLimit();
+			$this->checkThrottleLimit();
 
 			$item['gravity']     = Item::GRAVITY_PARENT;
 			$item['object-type'] = Activity\ObjectType::NOTE;

src/Module/Api/Twitter/Statuses/Update.php

@@ -121,7 +121,7 @@ class Update extends BaseApi
 			$item['gravity']     = Item::GRAVITY_COMMENT;
 			$item['object-type'] = Activity\ObjectType::COMMENT;
 		} else {
-			self::checkThrottleLimit();
+			$this->checkThrottleLimit();
 
 			$item['gravity']     = Item::GRAVITY_PARENT;
 			$item['object-type'] = Activity\ObjectType::NOTE;