update gosdk/io to v6
add rsf for v6
change  conf.UP_HOST to http://up.qiniu.com
recover rpc.logger support
Merge branch 'feature/update_io_to_v6' of github.com:wangtuanjie/api into feature/add_rsf_for_v6
add  rpc.logger support
fix unit test
fix api.io
fix ploicy.Expires buf
fix policy.Token() bug
Merge pull request #72 from wangtuanjie/feature/fix_policy_expires_bug

fix policy.Token() bug
wMerge remote-tracking branch 'qiniu/develop' into feature/update_io_to_v6
update
Merge pull request #67 from wangtuanjie/feature/update_io_to_v6

update gosdk/io to v6
Update io_api.go
Merge branch 'feature/update_io_to_v6' into feature/add_rsf_for_v6
fix bucker could be nil bug
EOF support
fix
Merge pull request #68 from wangtuanjie/feature/add_rsf_for_v6

Feature/add rsf for v6