Fix get openid error

Fix: get header error

Merge branch 'master' of github.com:tencentyun/wafer-php-server-sdk

fix bug (#5)

* fix bug

* add pdo port

fix bug (#5)

* fix bug

* add pdo port

更新 API 文档

update `license-image` icon link

remove redundant `}` character

Update README.md

do some cleanup