Merge pull request #15 from wenzhihong2003/master

修改canal.properties里的canal.address为canal.ip
fixed issue 16 #16
1. 增加isUpdate判断，基于before/after值
2. 修复isNull字段丢失
3. 修复sqlType值为0的情况
fixed #17 Remove null-terminate checking for VARCHAR/CHAR type.
Signed-off-by: in355hz<in355hz@gmail.com>
Merge branch 'master' of https://github.com/AlibabaTech/canal
fixed issue #18
1. 针对text类型，反查table meta获取数据库真实字段信息，然后进行编码转化处理
Merge pull request #1 from alibaba/master

合并原作者更新