v0.8.9

Features

• delete unnecessary observer to adapt old version browers (869963c)
• localisation support (7ca12b7), closes #217
• 增加有序列表、无序列表按钮 (f52ff42)

Bug Fixes

• #357 优化z-index的取值 (729b404)
• #358 (56ceedc)
• issue 350 (ebce611)
• 修复无浏览器模式报错 #353 (5571a4f)