release version 2.0.16

Author: cebe

composer.json

@@ -12,7 +12,7 @@
  "irc": "irc://irc.freenode.net/yii",
  "source": "https://github.com/yiisoft/yii2"
  },
- "minimum-stability": "dev",
+ "minimum-stability": "stable",
  "require": {
  "php": ">=5.4.0",
  "yiisoft/yii2": "~2.0.14",