[ticket/14875] Add method for raw input to request and add to installer

A method for retrieving raw input has been added to the request class.
This will be used in the installer to retrieve the datatabase password
while also allowing utf8 characters. Not escaping the input is ok in
this case as it won't be put anywhere in this raw form and only be
used to populate the entry for the password field in config.php.

PHPBB3-14875

phpBB/phpbb/install/helper/iohandler/iohandler_interface.php

@@ -38,6 +38,17 @@ interface iohandler_interface
 	 */
 	public function get_input($name, $default, $multibyte = false);
 
+	/**
+	 * Returns raw input variable
+	 *
+	 * @param string	$name		Name of the input variable to obtain
+	 * @param mixed		$default	A default value that is returned if the variable was not set.
+	 * 								This function will always return a value of the same type as the default.
+	 *
+	 * @return mixed	Value of the raw input variable
+	 */
+	public function get_raw_input($name, $default);
+
 	/**
 	 * Returns server variable
 	 *