add base64Decode and fix PutPolicy Expire
fix
fix
Merge pull request #84 from icattlecoder/feature/base64decode

add base64Decode and fix PutPolicy Expire
add saveKey,insertOnly,fsizeLimit,detectMime, persistent to put Policy
add Putpolicy marshal unit test
fix
fix
Merge pull request #85 from icattlecoder/feature/add-putPolicy-feild

add saveKey,insertOnly,fsizeLimit,detectMime, persistent to put Policy
修改为上传时到行为
1.key为null，则key最终为etag
2.将方法调用统一到put，保留以前到方法
resolve conflict