* switch to composer for qrcode and otp dependencies

* move most OTP-related stuff into userhelper
* remove old phpqrcode and otphp libraries

vendor/chillerlan/php-settings-container/src/SettingsContainerInterface.php

@@ -0,0 +1,104 @@
+<?php
+/**
+ * Interface SettingsContainerInterface
+ *
+ * @filesource   SettingsContainerInterface.php
+ * @created      28.08.2018
+ * @package      chillerlan\Settings
+ * @author       Smiley <smiley@chillerlan.net>
+ * @copyright    2018 Smiley
+ * @license      MIT
+ */
+
+namespace chillerlan\Settings;
+
+use JsonSerializable;
+
+/**
+ * a generic container with magic getter and setter
+ */
+interface SettingsContainerInterface extends JsonSerializable{
+
+	/**
+	 * Retrieve the value of $property
+	 *
+	 * @param string $property
+	 *
+	 * @return mixed
+	 */
+	public function __get(string $property);
+
+	/**
+	 * Set $property to $value while avoiding private and non-existing properties
+	 *
+	 * @param string $property
+	 * @param mixed  $value
+	 *
+	 * @return void
+	 */
+	public function __set(string $property, $value):void;
+
+	/**
+	 * Checks if $property is set (aka. not null), excluding private properties
+	 *
+	 * @param string $property
+	 *
+	 * @return bool
+	 */
+	public function __isset(string $property):bool;
+
+	/**
+	 * Unsets $property while avoiding private and non-existing properties
+	 *
+	 * @param string $property
+	 *
+	 * @return void
+	 */
+	public function __unset(string $property):void;
+
+	/**
+	 * @see SettingsContainerInterface::toJSON()
+	 *
+	 * @return string
+	 */
+	public function __toString():string;
+
+	/**
+	 * Returns an array representation of the settings object
+	 *
+	 * @return array
+	 */
+	public function toArray():array;
+
+	/**
+	 * Sets properties from a given iterable
+	 *
+	 * @param iterable $properties
+	 *
+	 * @return \chillerlan\Settings\SettingsContainerInterface
+	 */
+	public function fromIterable(iterable $properties):SettingsContainerInterface;
+
+	/**
+	 * Returns a JSON representation of the settings object
+	 * @see \json_encode()
+	 *
+	 * @param int|null $jsonOptions
+	 *
+	 * @return string
+	 */
+	public function toJSON(int $jsonOptions = null):string;
+
+	/**
+	 * Sets properties from a given JSON string
+	 *
+	 * @param string $json
+	 *
+	 * @return \chillerlan\Settings\SettingsContainerInterface
+	 *
+	 * @throws \Exception
+	 * @throws \JsonException
+	 */
+	public function fromJSON(string $json):SettingsContainerInterface;
+
+}