Use querystring lib and delete generateQuerystring() function
Update CHANGELOG file.
Create version 2.4.3
Add custom return body support
Update return body support
Merge pull request #52 from ikbear/hotfix/use_querystring

Use querystring lib and delete generateQuerystring() function
Merge pull request #53 from ikbear/feature/support_returnbody

Add custom return body support
Release v2.4.3
Merge pull request #55 from ikbear/release/v2.4.3

Release v2.4.3
Merge pull request #54 from qiniu/develop

Release v2.4.3