Add RequestInterface::getPost to ensure correct code completion in IDE

src/RequestInterface.php

@@ -11,4 +11,12 @@
 
 interface RequestInterface extends MessageInterface
 {
+    /**
+     * Return the parameter container responsible for post parameters or a single post parameter.
+     *
+     * @param string|null           $name            Parameter name to retrieve, or null to get the whole container.
+     * @param mixed|null            $default         Default value to use when the parameter is missing.
+     * @return \Zend\Stdlib\ParametersInterface|mixed
+     */
+    public function getPost($name = null, $default = null)
 }