[fix]by Jinqn修改背景颜色和粘贴图片的bug
Merge branch 'dev-1.3.0' of https://github.com/campaign/ueditor into dev-1.3.0
merge
[fix]by Jinqn修改seciton、background、music插件
[fix]by Jinqn修改music插件的插件
[fix]by Jinqn修改background的bug
[fix]by Jinqn
[fix]by Jinqn目录大纲支持undo、redo触发事件
Merge pull request #58 from Jinqn/dev-1.3.0

Dev 1.3.0 修复新功能和音乐插件的bugs