Merge pull request #375 from supermp/master

让Request支持json方式的POST

library/think/Request.php

@@ -686,8 +686,13 @@ class Request
     public function post($name = '', $default = null, $filter = '')
     {
         if (empty($this->post)) {
+            $content = $this->input;
+            if (empty($_POST) && strpos($content, '":')) {
+                $this->post = json_decode($content, true);
+            } else {
                 $this->post = $_POST;
             }
+        }
         if (is_array($name)) {
             $this->param       = [];
             return $this->post = array_merge($this->post, $name);