Merge pull request #2 from sneezry/master

对齐版本
Merge branch 'master' into develop
修复群消息显示的发送时间始终为打开窗口时的时间的问题
Merge branch 'hotfix/groupMessageTime' into develop
Merge branch 'hotfix/groupMessageTime'
Merge branch 'develop'
Merge pull request #29 from TooooBug/master

修复群消息显示的发送时间始终为打开聊天对话框时间的bug